L I BEAR"? ¢ T A 8: M COLLEGE. CAMPUS . R7l-337-8m TEXAS AGRICULTURAL EXPERIMENT STATION A. B. CONNER, DIRECTOR COLLEGE STATION, BRAZOS COUNTY, TEXAS BULLETIN NO. 541 APRIL, 1937 DIVISION OF HORTICULTURE FACTORS AFFECTING THE AMOUNT OF PUFFING IN TOMATOES AGRICULTURAL AND MECHANICAL COLLEGE 0F TEXAS T. O. WALTON, President The use of varieties and strains with a high proportion of normal fruit and the development of new low pufling varieties is the best solution of the problem of pufliness in tomatoes. Certain strains of Bonnie Best, Earliana, Kanora, Marketeer, Stone, and Success have been found to have a small amount of puff and are among the varieties being used as parents in breeding work to develop strains with a smaller proportion of pufled fruit. Seed from plants selected for a small amount of pufling produced plants which yield- ed fruits with decidedly less pufl’ than the seed selected from plants with a large proportion of puffed fruit. Crossing of varieties tends to reduce puffing, as indicated by the behavior of inter-varietal crosses which show about the same amount of pufi as the parent having the smaller amount of pufl‘. Multiple crosses further decrease the tendency to pufi, as shown by crossings involving four varieties the first generations of which developed less pufling than those involving any two varieties. Factors found to affect the proportion of to-mato fruits puffed involve variety and strain (hereditary), pollination, available water, temperature, and general nutritional conditions. One or more of these factors may be influenced also by soil type, which in this way may be said to have an influence on the amount of puffing. There appears to be a critical period early in the develop- ment of many fruits during which one or more of these factors have an especially important effect. Temperatures above 100°F. increase puifing to approximately 100 per cent, possibly by a re- duction in~ germination and growth of pollen. ‘Vhen maximum temperatures remain below 100°F., lower minimum temperatures appear to favor normal fruit development. Less puff has been found with less available water, and more puff with a greater water supply. On poor sandy soil the addition of commercial fertilizer has reduced the proportion of puif. This was not true on more fertile soil. Most small-fruited varieties have very little puff. Varieties with globe-shaped fruits and few seed cavities are more inclined to plifi than varieties with oblate fruits and many seed cavities. Very large fruits that tend to be fasciated are likely to be puffed. TABLE OF CONTENTS Page Introduction 5 Extent of variation 6 Procedure 7 Results 8 Available Water 8 Greenhouse experiments 8 Irrigation 1 2 Sprays 14 Rainfall > 1 5 Discussion 2 6 Temperature 2 9 Soil 3 2 Fertilizers 3 4 Supplements _ 39 Discussion 3 9 Disease 4 0 Southern blight 40 Blossom end rot- 4 1 Pollination 4 1 Position of fruit 4 2 Hereditary factors __.- 4 4 Varieties and strains 4 4 Selections 5 5 Crosses 5 7 Discussion 6 0 Summary 6 1 Literature cited 6 4 BULLETIN NO. 541 APRIL, 1937 FACTORS AFFECTING THE AMOUNT OF PUFFING IN TOMATOES S. H. Yarnell, Chief, Division of Horticulture; W. H. Friend, Superintendent, and J. F. Wood, Horticulturist, Substation No. 15, Weslaco. As early as 1895 in a variety report 0n tomatoes by H. Ness (12) appears the following comment on the fruit of the Terra Gotta: “(it) is rather a semi-capsule with a leathery covering, reminding one of a pod of sweet pepper rather than of an ordinary tomato” (D. 647). This is an accurate and graphic description of a severe type of what is now common- 15v called tomato “puff” or “pops”. In defective fruits the seed-bearing tissue does not fill the area within the outer walls completely. In addition, the cross walls may become hard and unpalatable and sometimes grow so as to fill the fruit. Severely affected fruits can be readily identified without cutting because they are angular in shape and somewhat lighter in weight. Figure 1 illustrates these abnormalities. A more detailed description has been published by Traub, Hotchkiss, and Johnson (20). The defective condition has been observed in the field by Taubenhaus and Ezekiel (17) and by the present writers as soon as the fruit is large enough for examination with a hand lens. Fruits that seem to have developed the defect at a considerably later stage are sometimes found. While it is difficult to get an accurate estimate, it is believed that a high proportion of the affected fruits develop the condition at an early stage. After careful investigation Taubenhaus and Ezekiel (17, 18) and later Taubenhaus and Altstatt (19) conclude tentatively that the trouble is probably not the result of activity within the plant of a virus or other disease-producing organism. A study of the effect of hereditary and various environmental factors seems to bear this out. One of the earliest attempts to find a cause for pufiing in tomatoes was made by Sando (14) working in Florida in 1919. The investigation, which does not seem to have been carried beyond a preliminary stage, was reported in an appendix to a paper on ripening in the tomato. In a. single random crate at a packing house he found 32 normal, 56 partially hollow, and 66 severely puflied fruits. He examined fruit in the field and found that a single plant may have both normal and puffed fruits. He also observed that “there is no stage in the life history of the tomato at which pufliness is a natural occurrence, but it may occur on small as well as large fruit.” His work with fertilizers will be discussed later. Since the condition is much worse for the same varieties in Florida than in Michi- gan, he concludes that “the phenomenon is probably physiological in its nature . . . .” He suggests further that the defect may be due to somatic variation. 6 BULLETIN NO. 541, TEXAS AGRICULTURAL EXPERIMENT STATION An interesting phase of the situation lies in the fact just mentioned, that it seemsto be more severe in the South than farther north. It has been referred to in publications of the Arkansas (21), California (10), Florida (22), and Texas stations, and of the United States Department of Agriculture (13). It is an important source of loss to growers of early fruit in this State. The loss from this source has been estimated to be from 5 to 35 per cent of the commercial crop. Extent of Variation In a rather extended investigation of pufiing in tomatoes it has seemed that the most consistent factor is the high amount of variation obtained. The amount of puffing among different lots may range from 0 to as much as 80 per cent or more, depending upon variety. Different strains of the same variety grown under comparable conditions have ranged from 36 to 77 per cent puff. The same lot may have as high as 78 per cent puff Figure 1. Types of puffing. during one part of the season and as little as 15 per cent at another period. Similar variations occur for the same strain over a period of several seasons. This large amount of variation is interpreted to mean that, in addition to the usual amount of variability due to chance sampling, the expression of the defect or characteristic is readily influenced by a large number of factors-hereditary and environmental. These factors may be expected to be interdependent. The immediate problem thus becomes one of de- p termining what the factors are and of estimating their relative impor- tance. Certain evidence has been presented (6, 25) to show that there are important varietal differences Which have a hereditary basis. This subject will receive further attention here, as will the results of a study of a number of environmental factors. The latter are harder to identify since they are difficult to control without special equipment. Among en- vironmental factors that might be expected to be of consequence in de- termining the amount of pufling are available moisture, temperature, humidity, fertility and character of the soil, and amount of wind and sunshine. Q FACTORS AFFECTING THE AMOUNT OF PUFFING IN TOMATOES 7 Procedure In an attempt to evaluate the relative importance of the various fac- tors concerned, a number of varieties and strains have been grown in field plats for comparison both at the Main Station in east central Texas and at Substation No. 15 in the Lower Rio Grande Valley. In addition, tests were made of the effect of certain fertilizers and sprays and of vary- ing the water supply. A study of- the effect of different weather conditions has also been made. At College Station, plants were started in a greenhouse, transferred to flats, and set in the field after serious danger of frost was past. All varieties were planted and set in the field at approximately the same time. In a few cases seed received late was planted after the rest. The 1931 planting was earlier than the others. The number of plants per lot varied considerably during different seasons and among the various lots. For the 1935 season 25 plants were grown; this was reduced to 20 in 1936. In certain cases fewer plants were grown because of lack of mate- rial. Rows were spaced 3 feet apart with plants 24 or 30 inches in the row. At Substation No. 15 in the Lower Rio Grande Valley seed was planted in an outdoor seed-bed and the plants were later transferred to a field previously irrigated. The plat consisted of 10 to 25 plants, depending on the type of test. All plants were grown under irrigation as a spring or fall crop. The plants were not pruned or staked in the field at either location. In the process of securing data each fruit was cut transversely a little nearer the stem than the blossom end and graded according to the severity of the condition. The stage of development of the fruit at time of examination varied somewhat. Much of the fruit was examined before reaching the green-ripe stage, the stage at which it is gathered commer- cially for early shipment, although data were taken occasionally on older fruits. While it is more diflicult to make an accurate classification of ripe fruit because of softness, it will be shown later that, for purposes of comparison, it is more important to use fruits developing over the same period than to examine any particular stage. In. examining the data from the various lots as to possible causes for the variation found, it is first necessary to determine whether or not the difference between any two lots is greater than could be due to chance. The chi square test of independence as outlined by Fisher (4) was found to be a convenient means of determining the significance of such dif- ferences in the amount of pufiing between two lots. The numbers of normal and puffed fruits for each lot provide data for a four-fold table from which chi square is calculated according to the following formula: Ch. _ (ad——bc)2(a+b+¢+d) ‘Sq“a’e" I a and b representing the numbers of normal and puffed fruits of one lot and c and d the corresponding numbers of the lot with which the first is 8 BULLETIN NO. 541, TEXAS AGRICULTURAL EXPERIMENT STATION being compared. With a value of 5.4 for chi square the chance is 50 to 1 that the difference between lots is not due to chance but is significant. In most of the tables percentages were not calculated when there were less than 3O fruits per lot. Most lots had between one and five hundred fruits; a few had more. Where fruit numbers are not given, percentages with the superscript (1) had between 5O and 99 fruits; those with (2) had between 3O and 49. In such cases the number of fruits has already been published (25). RESULTS Available Water As is usual in dealing with a plant characteristic responsive to several factors, it has been found diflicult to limit the number of variable factors. Observations were made on fairly well controlled moisture experiments in the greenhouse, on less well controlled irrigation experiments in the field, and on the pufling response of tomatoes to different amounts of rainfall. Greenhouse Experiments: These were carried out at College Station. A comparison was first made between lots receiving two different amounts of water applied in the usual way. Cuttings of Norton Wilt-resistant were grown in galvanized containers 10 inches in diameter and 9 inches deep. The plants were pruned to two stems and staked. The flowers were polli- nated by hand. There were eight rows of four plants each. Alternate rows were given the same treatment. The differential waterings began January 13, 1934, and continued to the end of the experiment. The plants watered heavily received, altogether, 213 liters, while those watered lightlry were given a total of 130 liters. Fruits were cut when about one- half inch in diameter. The data are summarized in Table 1. The difference was great for the initial cutting, but the number of fruits was very limited, It will be noted that the percentages of puff based on total fruits are just about Table 1. Diiferential Water treatments, spring 1934. Based on available fruit for each period. Heavy applications Light applications Data taken Number Number % Number Number % normal puffed puffed normal puffed pufied February 16 . . . . . . . . . . . . . . . 0 7 100 5 5 50 February 21-22 . . . . . . . . . . . . 9 19 68 7 16 70 March 2 . . . . . . . . . . . . . . . . . . 13 24 65 13 21 62 March 13 . . . . . . . . . . . . . . . . . 2S 48 67 9 49 84 Total . . . . . . . . . . . . . . . 47 98 67.6 35 91 72.2 Average . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 75 . . . . . . . . . . . . . . . . . . .. 66.5 the reverse of those obtained by averaging the percentages for each period. This is due to the greater weight of the larger numbers of fruits at the later pickings. If a sample of dependable size had been obtained at each picking, the average amount of puff for each treatment would FACTORS AFFECTING THE AMOUNT OF PUFFING IN TOMATOES 9 have been a more useful figure than the percentage based on total fruit. The alternate flooding and drying out of the soil necessitated by the method of watering would be expected to cover up at least in part any difference due to the differential treatments. Since the amount of water available to both groups varied widely at different times, the possibility of a constant Water supply suggested itself. Plants were grown in vitrified tiles standing in water at different depths, this being the only source of water. In no case was there an attempt to control such factors as temperature, relative humidity, and amount of light. Changes in these factors were presumably the same for all lots. The amount of water available was regulated by the distance to water. The water level is termed “water table” for convenience. The vitrified tile measured 8 inches inside diameter and 38.5 inches long. The flanged end was covered with screen to reduce seepage of soil into the Water. The soil was mixed all together with an addition of sand and well-rotted manure. The plants were cuttings of Globe and were carefully graded, each lot of five plants receiving equal numbers of each grade. The ex- periment was set up November 10, 1934. The plants were pruned to a single stem and trained on a string fastened to wires above, one side branch being allowed to develop later. All flowers were hand pollinated as before. Figure 2 was made at the time flowers began to develop. It can be seen that the three middle rows were developing faster than the lot with Figure 2. Differential water treatments in the greenhouse. the lowest water table. The plants with the highest water table were seriously handicapped. In fact, they grew little more than this during the remainder of the experiment. Free water stood on the surface of the soil of this lot on warm afternoons. The surface of the soil of the lot in the second highest water table showed evidence of moisture at all times. The soil surface of the lot with the lowest water table was fairly dry at 1'0 BULLETIN NO. 541, TEXAS AGRICULTURAL EXPERIMENT STATION all times. The water containers were kept full, no water being added to the top of the tiles after setting. While the data are not extensive, there is a decided trend toward in- creased puffing with a greater water supply (Table 2). By far the great- Table 2. Differential water treatments—-winter 1934-35. Based 0n total available fruit. Distance* to Number Number Per cent water (in.) normal puffed puffed 33 2 1 20 49 29 1O 36 78 22 7 31 82 1 7 8‘ 3S 8 l 5 O 6 100 *From top of tile. est difference appears between the lot with the lowest water table and the others. The lot with the highest water table has considerably more puff than the others, but the number of fruits is so small as to be of value only as an indication. A comparison of the different lots is made in Table 3. The lot having the highest water table is not included be- Table 3. Comparison of differential water treatments-flvinter 1934-35. Lots compared Values of* chi square Water table (in.) 33 —- 29 8.22 33 —- 22 9.27 33 — l7 9 . 87 29 ——- 22 O. 14 29 —— 17 0. l3 22 —— 17 0.0004 *Va1ues of 5 or more are considered significant. cause of lack of data. When the lot with the lowest water table is com- pared with the other three we find a significant difference in each case. When the other three are compared among themselves we find no sig- nificant difference. ~ The third greenhouse experiment, quite similar in setup to the second, was carried out during the spring of 1935. The soil had been left in the tile and was used again without removing. Because of the lack of differ- ence between the three lots with an intermediate distance to the water table, the two highest were made the same and the third was made about the same as the lowest, to give two rows with a low water table and three rows with a relatively high water table. The surface of the water was approximately 33 inches below the top of the tile for the former as before, and about 10 inches for the latter. Seedlings of Master Marglobe (lot 434), the same as _those of the field check this season, were used. The plants were graded according to size and distributed among the different rows as before. In addition to this, 10 plants were grown in 10-inch pots FACTORS AFFECTING THE AMOUNT OF PUFFING IN TOMATOES 11 and 15 plants were grown in 4-inch pots. These were Watered in the usual manner. The opportunity for the soil to dry out between waterings considerably reduced the amount of water available to these plants. In addition the amount of soil was considerably reduced, particularly in the case of the plants in the 4-inch pots. The experiment was set up April 8, 1935. The plants were pruned to a single stem and were sup- ported with strings as before. All flowers were hand pollinated. The fruits from the high water table lot and those from plants in 10-inch pots were examined when they were between three and four centimeters in diameter. Fruits from the other two were examined when between two and three centimeters in diameter, since it was at first thought that fruits from the lots lacking an abundant water supply might develop slower than the others. This was not the case. Results, based on total numbers of fruits, are presented in Table 4, with comparisons in Table 5. The difference in the amounts of puff Table 4. Differential water treatments-spring 1935. Based 0n total fruit for season. Number Number Per cent Treatment normal puffed puffed 4-inch pots . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 16 39 10-inch pots . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 70 62 Low water table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 210 85 High water table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79 ' 312 80 between plants in 4-inch and in 10-inch pots is probably significant, although the value of chi square is low because of the small numbers of fruits from the former group. Plants in pots all had a decidedly lower amount of puff than those in tiles. The two lots having different Water Table 5. Comparison of differential water treatments—spring 1935. Based on total fruits for each lot. Values of* Lots compared chi square 4-inch pots—10-inch pots . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.4 4-inch pots—-low water table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 . 1 4-inch pots-high water table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33.6 ' 10-inch pots—low water table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24. 7 10-inch pots-high water table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 .1 Low water table-high water table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.2 ‘Values of 5 or more are considered significant. tables did not have a significant difference in amount of pufi, presumably "because of two things. The plants with the low water table grew off rapidly and established contact with moist soil at a comparatively early "date, thus greatly reducing the difference in the amount of available gmoisture between the two lots. Conditions were favorable for this com- éparativelvy rapid development because of the high humidity accompanying ffan unusual amount of rainy weather during May, the total rainfall this ijmonth amounting to 10.29 inches instead of the 4.67 inches which is the 12 BULLETIN NO. 541, TEXAS AGRICULTURAL EXPERIMENT STATION 46-year average for College Station. There was little difference in size of plant between the two lots. During the preceding winter there had been a noticeable size difference between plants with the lowest water table and the others. The second point of explanation has to do with the effect of the high temperature in the greenhouse during late spring and early summer. The results will be discussed in detail under this head. Irrigation: These experiments were carried out at Substation No. 15, Weslaco. Plats of Cooper’s Special were given difierential irrigation treatments during the spring of 1928. The plants were grown on Fili- gonio fine sandy loam. Water was applied by means of an overhead sprinkler system, the amount measured by the use of eight rain gauges. The irrigations were given during March, April, and May. There was .18 inch of rain during March and .66 during April. The May irrigation was made on the first day of the month. A two-inch rain fell on the fifth with a total for the month of 7.44 inches. This nullified the differential treat- ments for this period. The data are presented in Table 6. Table 6. Dilferential irrigation treatments—spring 1928. Percentage of pufled fruit. Treatment prior to May 1 (inches) Data taken ' 2.61 7.04 4.52 4.52 5.71 5.71 5.16 5.16 June7 . . . . . . . 27 23 31 26 34 32 23 21* June 16 . . . . . . . . . . . . .. 12 11 16 21 19 41 26 21 *Between 50 and 99 fruits involved; other percentages based on over 100 fruits. If it is supposed that environmental factors have a greater effect during the early development of the fruit than later, the length of time required for fruit to develop to the stage at which it is examined is an important factor in interpreting results. Sando (14) found that it took 49 days for fruit of the Globe variety to develop to maturity at Arling- ton, Va., and 56 days for a winter crop at Peters, Fla. Jones and Rosa (8) cite Krassowska (9) as finding that a period of 54 to 65 days is neces- sary for fruit development in Poland. Fruits under about 35 days old would not be expected to show an influence of differential irrigation be- cause of the rain on May 5. While the ages of the fruits harvested on June 7 are not known, it seems possible that the lack of a consistent dif- ference between the various treatments might be due to the inclusion of a high proportion of fruits developing after May 5. Differential irrigations were again made during the 1934 season, This time three varieties were used: Chalk’s Jewel, Marglobe, and Pritchard. Each treatment was made in duplicate for each variety. One group re- ceived irrigation, the other did not. The plat in this experiment consisted of a single row of 20 plants. These plants were grown on the same piece of ground as before. The rows were 6 feet apart with plants 3 feet in the row. The plats receiving water were irrigated on September 25, October 10, and November 17. The rainfall in inches for the last four months of 1934 was 4.63, 1.01, 0.61 and 1.49. There was one rain of as FACTORS AFFECTING THE AMOUNT OF PUFFING IN TOMATOES 13 much as an inch in September, but the rest was distributed in fairly small amounts. Fruits an inch or more in diameter were harvested the first three pickings. All fruits down to one-quarter inch in diameter were harvested the last picking. The data, grouped according to pickings, are presented in Table 7. It will be noted that for the first picking the unirrigated plats have con- siderably less puff for each variety. Values of chi square are compara- tively low because of small numbers of fruit. With the exception of the Table 7. Differential irrigation treatments—fall 1934. Based on total fruit for each period. Irrigated Unirrigated Values* Variety Data taken chi No. No. Per cent No. No. Per cent square normal puffed puffed normal puffed puffed Chalk's Jewel Nov. 16 . . . . .. 51 15 23 25 5 17 2.25 Nov 26 . . . . . . 93 31 25 68 12 15 2.92 Dec 8 . . . . . .. 99 14 12 82 11 l2 0.015 Dec 20 . . . . .. 361 172 32 366 172 32 0.011 Total . . . . . . . . 604 232 28 541 200 27 O. 11 Average . . . . . . . . . . . . . . . . . . . . . . 23 . . . . . . . . . . . . . . . . 19 Marglobe Nov. 16 . . . . . . 3 13 81 12 6 33 4.83 NOV. 26 . . . . .. 16 22 58 7 18 72 1 .29 Dec. 8 . . . . . .. 64 32 33 54 23 3O 0.24 Dec. 2O . . . . .. 334 292 46 334 197 37 10.7 Total . . . . . . . . 417 359 46 407 244 38 11.9 Average . . . . . . . . . . . . . . . . . . . . . . 55 . . . . . . . . . . . . . . . . 43 Pritchard Nov. 16 . . . . . . 6 19 76 14 8 36 7 .52 Nov. 26 . . . . .. 33 21 41 13 27 68 7.53 Dec. 8 . . . . . . . 78 19 2O S5 23 3O 2 . 68 Dec. 2O . . . . .. 488 154 24 466 1S7 29 3 . 61 Total . . . . . . . . 605 213 26 548 245 31 4.66 Average . . . . . . . . . . . . . . , . . . . . . . 40 . . . . . . . . . . . . . . . . 41 ‘Based on numbers of fruits. Values of 5 or more are considered significant. second picking of Pritchard and the last picking of Marglobe the later pickings do not show a great deal of difference. The numbers of fruits are small in the case of the exceptional Pritchard data. A comparison of the percentages based on total fruit with the average of the percentages for each picking illustrates how a single heavy picking (December 20) , can dominate the season’s results based on total fruit. The value of the s‘ average, depending as it does upon the securing of sulficient fruit for an adequate sample at each picking, seems to be a better index in this case than that based on total fruit. During the 1935 season, plats of Gulf State Market, Pritchard, and Scarlet Dawn were given differential irrigation treatments. One group of plats received very light irrigation, one moderate, and one heavy. Data were obtained on October 28, and on November 4 and 14. The percent- , ages of puff based on total fruit harvested are given in Table 8. Gulf i‘ State Market made no consistent response. Pritchard had more puff with i? 5 V. 14 BULLETIN NO. 541, TEXAS AGRICULTURAL EXPERIMENT STATION Table 8. Differential irrigation treatments—fal1 1935. Pufling percentages based on total fruits harvested—-0ct. 10, Nov. 4, and Nov. 14. Type of irrigation Variety Degree of puffing Light Moderate Heavy Gulf State Market . . . . . . . Moderate . . . . . . . . . . . . . 16 19 12 _ Severe . . . . . . . . . . . . . . . 9 9.4 6.8 Both . . . . . . . . . . . . . . . . . 25 28 19 Pritchard ............. . . Moderate . . . . . . . . . . . . 12 2o 21 Severe . . . . . . . . . . . . . .. 4.2 8.9 12 Both . . . . . . . . . . . . . . . . . 16 29 33 Scarlet Dawn . . . . . . . . . . . Moderate . . . . . . . . . . . . . 25 27 23 Severe . . . . . . . . . . . . . . . 18 21 2S Both . . . . . . . . . . . . . . . . . 43 48 48 increased irrigation for both puffing classifications in about the same proportion. The proportion of moderately puffed fruits of Scarlet Dawn remained about the same while the proportion of severely puffed fruits of this variety increased with greater irrigation. During the fall of 1936 the irrigation treatments involved Marglobe and Rutgers. All lots were irrigated on September 2 and November 4. In addition, one lot of each variety was irrigated on October 7 and 24. The data may be found in Table 9. For the first two harvests there is Table 9. Differential irrigation treatments-—fall 1936. Pufling percentages based on 100 fruits each harvest. Harvest dates Variety November 20 December 3 December 19 Mod. Sev. Total Mod. Sev. Total Mod. Sev. Total Marglobe 2 irrigations 32 2 34 16 4 2Q 1O 2O 30 4 irrigations 8 6 14 12 4 16 24 34 _ 58 Rutgers 2 irrigations 10 2 12 14 8 22 20 14 34 4 irrigations 2 0 2 12 4 16 16 32 48 less puff on those plants receiving the extra irrigations. For the last harvest the situation is reversed. Judging by the values of chi square the percentages for the first two harvest periods of Mar-globe are not significant, while the last one is (1.096, 0.27, and 15.9). The correspond- ing figures for Rutgers are 7.68, 1.17, and 4.05. Since yields of market- able fruit were determined for these plats, the fruits were harvested at about the green-ripe stage. If they took around 60 days to develop as is suggested above, the fruits of the last picking of both varieties set during the effective period of the differential irrigation treatments. Sprays: During the spring of 1933 two lots of tomatoes, representing duplicate plantings of six varieties were given differential spray treat- FACTORS AFFECTING THE AMOUNT OF PUFFING IN TOMATOES 15 ments, one consisting of a 3-3-50 Bordeaux mixture and the other of the same spray plus 1 gallon of Volk to each 85 gallons of Bordeaux. The application was made on April 24 and the fruits picked at the third harvest, May 22, were classified as» to amount of puff. As there was little or no rainfall, the plants Were irrigated on March 16, on April 19 and 25, and on May 4. Pufling results are presented in Table 10. It will be seen that in every case there was more puff Where Volk had been added to the Bordeaux spray. Judging by the values of chi square obtained there were sufficient fruits to give a significant difference only for Gulf State Table 10. Effect of differential spray treatments—-Weslac0, spring 1933. Based 0n marketable fruits harvested at third picking, May 22. Sprayed with Sprayed with Bordeaux Bordeaux and Volk . Va1ues* Variety chi of Number Number Per cent Number Number Per cent square normal puffed puffed normal puffed puffed Bonney Best . . . . . . . . . 118 46 28 23 15 40 1.91 Marglobe (a) . . . . . . . . . 43 89 68 6 26 81 2.35 Pritchard . . . . . . . . . . . . 9S 95 5O 29 58 67 6.81 Ferry's 100 . . . . . . . . . .. 127 42 25 71 39 36 3 . 64 Gulf State Market . . . . 63 52 4S 21 68 76 20.2 Marglobe (b) . . . . . . . . . 46 64 53 - 16 58 78 8.80 Morse 498 . . . . . . . . . . . . 106 74 41 66 58 47 0.96 I Total . . . . . . . . . . $98 462 43 232 322 58 30.8 *Values of 5 or more are considered significant. Market, Pritchard, and the second lot of Marglobe. When all lots are added together the difference between the two lots is highly significant. In ac- counting for this difference in amount of puff, it appears that it may be primarily an effect of available water. Wilson and Runnels (24) have found that an application of Bordeaux to tomatoes increases the transpiration rate, while an application of oil decreases transpiration. They also tried equal parts of Bordeaux and a 1 to 100 Volk spray. The latter also reduced the transpiration rate, but less than Volk alone. The mixture reported here had more than twice as much Volk as the one they used and presumably decreased the transpiration rate more, to give a wider differential. This difference in rate of transpiration seems to have affected the rate of puff- ing in the same way as a difference in soil moisture. A final conclusion can not be drawn, since slight soil differences were involved and the plats were not replicated. Rainfall: The circumstances of securing data in the field are such that the effect of changes in the Weather must be considered with care. For " example, grouping data from fruit set several days in succession may I cover up, at times, differences due to changes in climatic factors that i might otherwise be apparent. During most years at College Station there 5i’ is a marked decrease in available moisture with the advance of the sum- . mer season. Occasionally there is an effective rain in July, which pro- vides an abundance of available moisture. Rather wide difierences are lto be found between different seasons, but the amount of comparable material from a genetic standpoint is limited. Finally the work has not .-- rx'v,'v-v<< ., uv§.'“\~ ~04‘ 16 BULLETIN NO. 541, TEXAS AGRICULTURAL EXPERIMENT STATION advanced far enough to provide an adequate estimate of the effect of the various factors in all cases, particularly any cumulative effect as the season advances. It is believed, however, that a consideration of the data from this standpoint will aid in an understanding of variations in the amount of tomato puff. Data on rainfall and evaporation were secured at the Main Station agronomy farm, at a distance of about a mile and a half from the location of these experiments. This distance introduces a source of error, although probably not serious. These data arepgiven in Table 11. Table 11. Rainfall and evaporation-Jlollege Station. Type and month 1931 1932 1933 1934 1935 1936 Rainfall (in.): March . . . . . . . . . . . . . . . . .. 3.6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. April . . . . . . . . . . . . . . . . . .. 3.3 2.3 1.9 6.0 3 2 3.3 May . . . . . . . . . . . . . . . . . . .. 1.9 3.2 4.6 0.4 10 3 7.9 June . . . . . . . . . . . . . . . . . . .. 1.0 2.8 0.2 0.02 14 1.0 July . . . . . . . . . . . . . . . . . . .. 2.6 0.76 5.0 0.8 4 5 13.3 August . . . . . . . . . . . . . . . . .. 1.0 3.5 6.1 1.2 1 7 1.9 Evaporation (in.): arc . . . . . . . . . . . . . . . . .. 4.4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. April . . . . . . . . . . . . . . . . . .. 3.8 4.7 5 1 4.2 3 8 4.9 May . . . . . . . . . . . . . . . . . . .. 6.2 5.3 5 9 6.3 3 9 4.6 June . . . . . . . . . . . . . . . . . . .. 6.7 5.6 7 7 8.9 5 4 7.0 July . . . . . . . . . . . . . . . . . . .. 6.2 7.6 7 2 9.3 6 9 6.0 August . . . . . . . . . . . . . . . . .. 7.1 6.8 6 1 8.0 7 3 6.4 The percentages of puff observed at College Station during May and June 1931, as presented in Table 12, reveal that there has been either less puff later in the season or no significant change. For 1931 there is Table 12. Comparison of varieties and period of fruit development—College Station, 1931. Based 0n total fruit for each period. May June Va1ues* Significant Variety % puff % puff of chi sq. change Bonny Best . . . . . . . . . . . . . . . . . . . .. 24 23 0.015 O Break O'Day . . . . . . . . . . . . . . . . . . . 38 20 40.9 ——- Cooper's Special . . . . . . . . . . . . . . . . . 78 15 168.2 — Earliana . . . . . . . . . . . . . . . . . . . . . .. 29 .9 33 0.97 0 Fargo . . . . . . . . . . . . . . . . . . . . . . . . . . 25 16 12.3 — Gulf State Market . . . . . . . . . . . . . . . 33 11 31.6 - June Pink . . . . . . . . . . . . . . . . . . . . .. 18 16 0.66 O Marglobe . . . . . . . . . . . . . . . . . . . . . . 64 62 4.0 ——(?) Total . . . . . . . . . . . . . . . . . . .. 37.0 25.5 12.5 -— * Values of 5 or more are considered significant. little difference in rainfall and amount of evaporation between May and June or little difference between March and April, but a marked differ- ence between April and May. The rainfall dropped from 3.3 inches in April to 1.9 in May While the accumulated evaporation rose from 3.8 in April to 6.2 in May. This would seem to give a considerably smaller amount of water available to the plant during May than during the pre- ceding month. It seems fair to assume that the fruits harvested in May thus set and developed under conditions providing more available mois- ture than those examined in June 1931. Only one variety had more puff FACTORS AFFECTING THE AMOUNT OF PUFFING IN TOMATOES 17 Table 13. Comparison 0f varieties and period of fruit development-—College Station, 1932. Based on total number of harvestable fruits for each period. Per cent puffed fruit Values3 Sig- Variety Lot June July 0f nifi- No. chi cant square change Mod. Severe Total Mod. Severe Total Acme . . . . . . . . . . . . . . . . . . . . . .. 67 16 4.3 20 8.2 0.1 8.4 41.7 — Bonny Best . . . . . . . . . . . . . . . . .. 7 26 4.2 31 22 1.0 23 3.20 0 Bonny Best . . . . . . . . . . . . . . . . .. 33 37 14 52 421 0.01 421 1.74 0 Bonny Best . . . . . . . . . . . . . . . . .. 39 23 6.2 29 15 0.0 15 18.1 -— Bonny Best . . . . . . . . . . . . . . . . .. 68 28 7.8 35 21 0.6 27 3.78 0 Break O’Day . . . . . . . . . . . . . . . . 2 39 11 5O 27 0. 3 27 46. 6 ——~ Break O'Day . . . . . . . . . . . . . . .. 14 46 5.2 52 33 1 . 7 34 14.7 -— Break O'Day . . . . . . . . . . . . . . .. 2O 38 10 49 26 0.0 26 43 . 3 —- Break O'Day . . . . . . . . . . . . . . . .. 43 39 11 5O 26 0.2 26 69.4 -— Cooper's Special . . . . . . . . . . . . . . 69 34 23 57 30 6.2 37 35.8 — Dwarf Champion . . . . . . . . . . . . . 70 32 8.7 40 22 0. 7 23 20.6 -— Earliana . . . . . . . . . . . . . . . . . . . . . 1 35 15 50 27 0.0 27 53.4 — Earliana4 . . . . . . . . . . . . . . . . . . .. 12 16 2.3 18 10 0.4 1O 6.91 —~ Earliana . . . . . . . . . . . . . . . . . . . . . 45 33 24 57 24 0.4 24 23 .9 -- Earl1ana4 . . . . . . . . . . . . . . . . . . .. 46 27 9.6 37 16 0.5 17 21.6 —— Early Detroit . . . . . . . . . . . . . . .. 5 21 6.8 27 15 0.5 15 33.5 ——- Early Stone . . . . . . . . . . . . . . . . . . 19 35 16 50 36 8.4 44 8.69 -— Globe . . . . . . . . . . . . . . . . . . . . . .. 8 35 26 61 33 5.5 39 18.2 —- Globe . . . . . . . . . . . . . . . . . . . . . .. 13 26 10 36 24 7.4 32 0.46 O Globe . . . . . . . . . . . . . . . . . . . . . .. 23 40 26 66 38 6.0 44 22 .8 — Globe . . . . . . . . . . . . . . . . . . . . . .. 72 31 46 77 39 18 57 8.92 —— Greater Baltimore . . . . . . . . . . . . 17 19 1.7 21 25 1.7 27 2.97 0 Greater Baltimore . . . . . . . . . . .. 31 24 2.7 27 27 1 . 7 29 0.577 O Gulf State Market . . . . . . . . . . . . 10 28 13 40 13 0. 7 13 62.1 ——- Gulf State Market . . . . . . . . . . . . 27 31 15 46 19 0.9 2O 20.5 ——- ~ Gulf State Market . . . . . . . . . . .. 32 36 16 53 24 9.7 34 18.5 —- Gulf State Market . . . . . . . . . . .. 73 19 5.5 24 11 1.4 13 24.1 —- John Baer . . . . . . . . . . . . . . . . . .. 6 22 3.5 26 13 0.0 13 32.8 -— Louisiana Pink . . . . . . . . . . . . . . . 37 22 24 46 32 14 45 0.0043 0 Marglobe5 . . . . . . . . . . . . . . . . . . . 3 42 24 67 53 15 68 3.87 0 Marglobe . . . . . . . . . . . . . . . . . . .. 11 242 582 822 471 321 791 0.159 0 Marglobe . . . . . . . . . . . . . . . . . . . . 15 45 ~30 74 46 16 61 37.96 -— Marglobe . . . . . . . . . . . . . . . . . . . . 24 57 16 73 49 8.3 58 7 .888 —— Marglobe . . . . . . . . . . . . . . . . . . . . 28 44 15 59 56 7.6 64 0.187 0 Marglobe . . . . . . . . . . . . . . . . . . .. 3Q 381 381 771 49 24 73 0.37 O Marglobe . . . . . . . . . . . . . . . . . . . . 4O 421 361 781 45 22 67 3.44 O Marglobe . . . . . . . . . . . . . . . . . . . . 41 37 46 83 47 23 70 40.1 —- Marglobe . . . . . . . . . . . . . . . . . . . . 44 46 25 71 49 9.5 59 29. 7 — Marglobe . . . . . . . . . . . . . . . . . . . . 47 48 28 76 49 16 66 4. 72 -— Marglobe5 . . . . . . . . . . . . . . . . . .. 55 321 231 551 47 9 .9 57 0. 113 O Matchless . . . . . . . . . . . . . . . . . .. 25 392 202 592 281 4.41 321 8.36 — Mississippi Girl . . . . . . . . . . . . . . 4 32 9.8 41 20 0.0 20 17.8 —- Norton . . . . . . . . . . . . . . . . . . . . .. 22 41 13 54 37 1.0 38 11.8 — Norton . . . . . . . . . . . . . . . . . . . . .. 35 41 18 58 27 0.0 27 7.66 Ponderosa . . . . . . . . . . . . . . . . . .. 75 562 142 702 381 0.01 381 12.0 —- Pritchard....» . . . . . . . . . . . . . . .. 49 .. .. .. 49 6.6 55 Stone . . . . . . . . . . . . . . . . . . . . . .. 9 35 8.3 43 28 1.5 29 13.3 ——- Stone . . . . . . . . . . . . . . . . . . . . . .. 16 .. .. .. 51 9.9 60 .. Stone . . . . . . . . . . . . . . . . . . . . . . . 76 3O 14 44 28 6. 5 34 7 .92 -— Success . . . . . . . . . . . . . . . . . . . . .. 21 26 3.7 30 20 3.8 24 1.01 . 0 Total“ . . . . . . . . . . . . . . . . . . . . . . 31 13 44 28 4. 7 33 44.0 -—- 1Based on between 50 and 99 fruits. 2Based on between 30 and 49 fruits. sBased on total numbers of normal and puffed fruits for each period. Values of 5 or more are considered significant. 4“June” data taken first few days in July. fiFertilized with 6-12-6 at the rate of 1800 lbs. per acre. 6T0ta1 only of lots harvested both months. 18 ‘ BULLETIN NO. 541, TEXAS AGRICULTURAL EXPERIMENT STATION Table 14." Comparison of varieties and period of fruit development—-College Station, 1933. Based on total number of harvestable fruits each period. Per cent puffed fruit Values3 Sig- Variety Lot July August of nifi- No. chi cant square change Mod. Severe Total Mod. Severe Total ’ Acme . . . . . . . . . . . . ..'. . . . . . . .. 103 17 0.0 172 14 0.0 14 0.29 0 Albino . . . . . . . . . . . . . . . . . . . . . . 42 38 6.3 442 64 0.0 641 3.59 +(?) Albino . . . . . . . . . . . . . . . . . . . . . . 194a 70 1.4 701 66 0.0 66 0.63 0 Albine . . . . . . . . . . . . . . . . . . . . . .. 194b 61 0.0 612 68 5.2 73 1.96 0 Bonny Best . . . . . . . . . . . . . . . . .. 33 7.7 0.3 8.0 15 0.2 15 9.82 + Bonny Best . . . . . . . . . . . . . . . . .. 39 9.6 1.9 121 17 0.0 171 0.65 0 Bonny Best . . . . . . . . . . . . . . . . .. 106 8.8 0.9 9.7 21 0.0 21 27.96 + Bonny Best . . . . . . . . . . . . . . . . .. 107 7.1 0.0 7.11 25 0.0 25 14.1 + Bonny Best . . . . . . . . . . . . . . . . .. 108 13 1.8 15 17 0.0 17 0.36 0 Break O’Day . . . . . . . . . . . . . . .. 20 26 8.6 35 27 0.0 27 4.83 ———(?) Break O’Day . . . . . . . . . . . . . . . . 43 19 2.7 22 30 0.0 30 5.87 + Break O'Day . . . . . . . . . . . . . . . . 112 26 3.2 301 25 0.0 251 0.47 0 Cherry, Red . . . . . . . . . . . . . . . .. 189 0.0 0.0 0.0 0.0 0.0 0.0 0 Cherry, Yellow . . . . . . . . . . . . . .. 188 0.0 0.0 0.0 0.0 0.0 0.0 0 Current, Red . . . . . . . . . . . . . . . .. 196 0.0 0.0 0.0 0-0 0.0 0.01 0 Cooper's Special . . . . . . . . . . . . .. 113 14 1.2 161 37 0.5 38 14-1 + Cooper’s Special . . . . . . . . . . . . . . 114 18 1.7 20 39 0.7 39 25.7 + Dwarf Champion . . . . . . . . . . . .. 115 18 2.7 20 19 0.5 19 0.22 0 Dwarf Champion . . . . . . . . . . . .. 116 12 1.7 13 19 0.0 19 2 .44 0 Dward Champion . . . . . . . . . . . .. 117 20 1.2 22 11 0.0 11 25.6 - Rarliana . . . . . . . . . . . . . . . . . . . . 118 19 2.7 21 26 0.0 26 1.14 0 Earliana . . . . . . . . . . . . . . . . . . . .. 119 12 0.0 121 17 0.0 172 0.65 0 122 12 0.0 121 .. 0.0 .. ——- .. 123 2S 1.1 261 16 0.0 161 2.66 0 Early Detroit . . . . . . . . . . . . . . .. 5 9.0 0.0 9.0 24 0.5 24 19.6 + Early Detroit . . . . . . . . . . . . . . .. 124 9.2 0.6 9.8 12 0.0 12 0.498 0 Early Detroit . . . . . . . . . . . . . . .. 127 10 1.5 121 6.4 0.0 6.4 1.58 0 Early Stone . . . . . . . . . . . . . . . . .. 164 15 2.8 18 56 2.9 59 178.9 + Early Stone . . . . . . . . . . . . . . . . .. 165 15 2.1 17 62 3.9 66 277.9 + Early Stone . . . . . . . . . . . . . . . . . . 166 20 0.8 20.4 54 3.0 57 127.5 + Early Tree . . . . . . . . . . . . . . . . . . . 197 30 0.5 31 29 0.2 29 0.83 0 Giant Climbing . . . . . . . . . . . . . . 195 39 0.0 391 83 0.0 831 36.6 + Globe . . . . . . . . . . . . . . . . . . . . . .. 130 27 0.0 272 40 0.0 40 3.15 +(?) Globe . . . . . . . . . . . . . . . . . . . . . .. 132 4. 0.8 5.4 11 0.0 11 5.47 + Globe . . . . . . . . . . . . . . . . . . . . . .. 135 32 2.7 35 32 3.4 361 0.002 0 Greater Baltimore . . . . . . . . . . . . 145 8.1 0.2 8.3 19 0.6 20 27.1 + Greater Baltimore . . . . . . . . . . . . 146 9.6 0.8 10 39 0.0 39 49.9 + Gulf State Market . . . . . . . . . . .. 10 2.9 1.5 4.41 38 0.0 38 27.0 + Gulf State Market . . . . . . . . . . . . 32 7.2 2 .1 9.2 28 0.0 28 38.5 + Gulf State Market . . . . . . . . . . .. 139 6.4 0.4 6.8 16 0.3 17 25.0 + Gulf State Market . . . . . . . . . . . . 140 16 0.8 17 40 0.8 41 75.9 + Gulf State Market . . . . . . . . . . . . 142 11 2.8 14 34 0.9 35 46.4 + Gulf State Market . . . . . . . . . . . . 144 7. 3.6 11 33 0.5 33 23. 1 + John Baer . . . . . . . . . . . . . . . . . .. 150 8.3 0.0 8.3 11 0.0 11 1.04 0 Kanora . . . . . . . . . . . . 26a 11 1.3 13 22 0.2 23 13.1 + Kanora . . . . . . . . . . . . . . . . . . . . .. 26b 18 0.0 181 36 0.7 37 7.20 + Karger . . . . . . . . . . . . . . . . . . . . .. 191 13 2.0 15 17 0.0 17 1.00 0 Lloyd Forcing . . . . . . . . . . . . . . .. 50 8.6 0.0 8.6 25 0.0 25 38.6 + Lloyd Forcing . . . . . . . . . . . . . . . . 51 9.1 2.3 11 29 0.5 29 21.2 + Lloyd Forcing . . . . . . . . . . . . . . .. 169 22 4.4 26 39 1.7 41 14.2 + LloydForcing . . . . . . . . . . . . . . .. 170 13 1.4 15 24 1.4 26 14.5 + Lloyd Forcing . . . . . . . . . . . . . . .. 171 12 1.1 14 28 0.0 28 21.2 + Lloyd Forcing . . . . . . . . . . . . . . .. 172 12 1.2 13 17 0.2 17 » 5.22 + Lloyd Forcing . . . . . . . . . . . . . . .. 187 2.9 0.9 3.8 24 0.0 24 23.8 + FACTORS AFFECTING THE AMOUNT OF PUFFING IN TOMATOES ' 19 Table 14. Comparison 0f varieties and period 0f fruit development-College Station, 1933. Based on total number of harvestable fruits each peri0d.—-C0ntinued Per cent puffed fruit Values3 Sig- Variety Lot July August of nifi- No. chi cant square change Mod. Severe Total Mod. Severe Total Marglobe . . . . . . . . . . . . . . . . . . .. 40a .. .. .. 54 1.0 55 ... —- Marglobe . . . . . . . . . . 40b 29 7 . 1 36 52 1 .1 53 20.2 + Marglobe . . . . . . . . . . . . . . . . . . . . 40c 28 7.0 35 47 0. 6 48 10.7 + Marglobe . . . . . . . . . . . . . . . . . . .. 40d 39 4.1 43 56 1.7 58 7.78 + Marglobe . . . . . . . . . . . . . . . . . . . . 41 3O 2.6 33 S0 0.4 50 28.1 + Marglobe . . . . . . . . . . . . . . . . . . .. 152 21 0.0 21 25 0.6 25 0.95 0 Marglobe . . . . . . . . . . . . . . . . . . .. 153 30 9. 3 402 51 0.0 511 1.34 0 Marglobe . . . . . . . . . . . . . . . . . . . . 154 34 0.0 342 33 0.0 332 0.03 0 Matchum . . . . . . . . . . . . . . . . . . .. 1S8 12 0.4 13 25 0.7 26 18.9 + Matchum . . . . . . . . . . . . . . . . . . . . 159 19 0.0 192 23 0.0 23 1.08 0 Mexican Husk . . . . . . . . . . . . . .. 192 3.7 0.0 3.7 2 4 0.0 2.4 0 52 0 Norton . . . . . . . . . . . . . . . . . . . . .. 35 17 0.0 171 18 0.0 18 0.021 0 Norton . . . . . . . . . . . . . . . . . . . . .. 160 19 1.4 20 46 1.8 48 75.2 + New Self Pruning . . . . . . . . . . . .. 181 2.3 0.0 2.32 36 1.7 37 19.3 + Peach . . . . . . . . . . . . . . . . . . . . . .. 179 4.4 0.3 4.7 32 0.0 32 92.1 + Pear, Italian . . . . . . . . . . . . . . . .. 183 2.7 0.4 3.1 5.5 0.0 5.5 1.59 0 Pear, Yellow . . . . . . . . . . . . . . . .. 180 0.0 0.0 0.0 0.0 0.0 0.0 0 Plum, Red . . . . . . . . . . . . . . . . . .. 189 .. .. .. 1.3 0.0 1.3 .. — Pritchard . . . . . . . . . . . . . . . . . . .. 162 29 1.1 301 58 0.0 58 15.6 + Pritchard . . . . . . . . . . . . . . . . . . . . 163 24 5.5 3O 49 1.5 3O 10.3 + Prune . . . . . . . . . . . . . . . . . . . . . .. 186 7.0 1.8 8.8 0.2 0.0 0.2 36.8 — Prune . . . . . . . . . . . . . . . . . . . . . .. 193 2.1 1.0 3.1 0.0 0.0 0.0 .. --(?) 1 Based on between 5O and 99 fruits. .~ 2Based on between 30 and 49 fruits. sBased on total numbers of normal and puffed fruits for each period. Values of 5 or more are considered significant. in June than during the preceding month and this slight increase was well within the limit of chance variation. This and two other varieties showed no significant difference. Four varieties, possibly five, had sig- nificantly less puff. The value of chi square for all eight varieties is 12.5, indicating a significant difference. This reduction in rainfall with increase in accumulated evaporation as the summer season progresses represents the usual trend at College Sta- tion. In 1932 when the data were secured in June and July instead of in May and June as before, we find that 46 out of 51 lots, representing 20 varieties, had less puff later in the season (Table 13). This difference was significant in 34 cases out of the 46. The other differences are not more than might be due to chance. There was a greater reduction in the amount of severely puffed fruits during the second harvest period than of those classified as moderately puffed. Even for those cases where there was little or no difference between the two periods in total amount of puff there was a much smaller proportion of severelfy puffed fruits later in the season (see Louisiana Pink and Total). This season (1932) the reduction in rainfall from May to June was less than in the preceding year but dropped to only .76 of an inch during July. The fruits harvested during July thus set and developed under progressively drier conditions than those harvested the preceding period. 2O ' BULLETIN NO. 541, TEXAS AGRICULTURAL EXPERIMENT STATION During 1933 the trend was reversed. In 39 instances there was a sig- nificant increase in the amount of puffing, with two additional lots that may have had a significant increase, In only 2 cases, including a small- fruited variety, was there a significant decrease; two others may be sig- nificant. Of the lots which did not change materially, 13 had a slight increase, 9 had a decrease, and 6 remained unchanged, 4 of which, being small-fruited, had no puff (Table 14). There was an unusually small amount of rainfall (0.24 inches) during June 1933, while during July there was an unusually large amount (5 inches). Fruits for the first period were cut from about June 10 to July 10, those for the second period from July 15 to August 10. Many of the fruits examined during the first period thus set and developed under much drier conditions than those examined during the second period. This general increase was for the most part due to an increase of mod- erately puffed fruit. Considering the class of severely puffed fruits we find a decrease from July to August in 44 cases, an increase in 12 cases, and no change in 18 lots. Table 15. Comparison of puffed fruit during three periods-Alollege Station, 1934. Based on total number of harvestable fruit for each period. June July Fall Per cent puffed Variety Lot _ . __~__ No. No. No. No. No. No. No. normal puffed normal puffed normal puffed June July Fall Bonny Best . . . . . . . . . . . . . 226 23 10 14 25 0 1 30 64 . . Bonny Best . . . . . . . . . . . .. 227 12 2 15 45* 159 72 .. 75 31 Bonny Best . . . . . . . . . . . . . 228 17 2 25 150* 105 41 . . 86 28 Dwarf Champion . . . . . . . . 241 16 7 49 19* 30 7 30 28 19 Early Detroit . . . . . . . . . . . . 245 15 1 23 22 14 6 . . 49 Globe . . . . . . . . . . . . . . . . . . . 129 8 0 1 5 15 28 . . . . 65 Globe . . . . . . . . . . . . . . . . .. 248 27 0 Z4 13 10 10 . . 35 .. Gulf State Market . . . . . . . 136 2 1 5 11 121 21 . . . . 15 Gulf State Market . . . . . .. 138 2 0 12 13 121 17 .. 52 12 Gulf State Market . . . . . . . 205 . . . . 0 3 114 49 . . . . 30 John Baer . . . . . . . . . . . . . .. 148 17 1 21 12 47 16 .. 36 25 Kanora. . , . . . . . . . . . . . . .. 201 2 0 3 7 137 16 .. .. 11 Lloyd Forcing . . . . . . . . . . . 279 9 1 3 20* 76 16 . . 87 17 *Includes data secured during the first few days of August. The 1934 summer season was exceptionally hot and dry. For this reason the amount of data was very limited and, since the observations were scattered over an unusually long period of time, comparisons are of doubtful value. As can be seen from Table 15, in many cases too few data were obtained for an accurate estimate of the amount of puffing for several lots during certain periods. It will be noticed that the percentage of puffed fruits developing during the dry period in the summer is, in general, greater than for fruits developing after the drought had been broken. There were 4.41 inches of rain during September, which stimu- lated the heaviest set of fruit that season. It seems likely that high temperatures rather than moisture differences may have been the de- FACTORS AFFECTING THE AMOUNT OF PUFFING IN TOMATOES 21 termining factors. The data will be considered further -under the subject of temperature. In order to determine the amount of variation to be expected from replicated plantings and to have a check for comparison with other lots, Stoke’s Master Marglobe (lot 434) was grown at regular intervals throughout the entire planting at College Station in 1935. The plats con- sisted of single rows of 25 plants each. The first plat of each row was lettered A in addition to the row number; the second plat of each row was lettered B, and so on. This lot of Marglobe occupied a plat in every sixth row, arranged so as to checker-board the field. Thus plats 2A, 8A, 5B, 11B, and so on, were Marglobe No. 434. The entire planting was 19 rows wide with 6 plats lengthwise across the field, the last group of plats having 15 instead of 25 plants. The soil is classified as Lufkin fine sandy loam. It is evident that it is slightly heavier at the eastern end of the field, including the F plats and a part of the E. The rest of the field appears to be quite uniform. The numbers and percentages of puffed fruits for these 17 replications are presented in Table 16. The data for the first pickings can be arranged Table 16. Replications of Marglobe 434—-C0llege Station, 1935. Based on total fruit for each period. First picking Second picking Per cent puffed PlatNo. Data Number Number Data Number Number taken normal puffed taken normal puffed First Second 2A June 11 38 97 July 12 208 106 72 34 8A " 13 45 137 " 12 326 101 75 24 SB " 13 33 134 " 15 290 126 80 3O 8C " 13 28 111 " 16 292 78 8O 21 11D ” 13 37 82 " 16 156 21 69 12 14E " 13 26 68 " 17 213 S0 72 19 14A " 17 63 147 " 12 181 178 7O 50 17B ” 25 111 99 " 16 76 40 47 35 2C " 26 140 151 " 16 127 148 52 54 5D " 27 131 109 " 16 36 22 45 38 17D July 1 109 65 ” 17 18 7 37 . . . . . 8E " 4 113 75 " 17 28 6 40 17 2E " 5 180 126 " 17 103 65 41 39 SF " 5 100 43 " 17 35 15 30 30 11F " 6 53 19 " 17 9 9 26 11B " 9 144 63 . . . . . . . . . . . . . . . . .. 3O 14C " 12 108 19 ' 16 6 7 15 . . . . . in four groups according to the date the records were taken. The amount of puff over the period June 11 to 17 inclusive ranges from 68.9 to 80.2 per cent with an average for seven plats of 74 per cent. Data gathered June 25, 26, and 27 have a lower percent of puff—from 45.4 to 51.9- with an average for the three plats of 48.2 per cent. Data for six plats were taken from July 1 to 9 inclusive. The range in this case is from 26.4 to 39.9 per cent, with an average of 34.1 per cent. The remaining plat had 15 per cent puff. 22 BULLETIN NO. 541, TEXAS AGRICULTURAL EXPERIMENT STATION A comparison between these figures and the rainfall five weeks previous is made in Figure 3. It will be seen that there is an ample amount of moisture early in the season, with a decreasing amount later, the decrease corresponding roughly to the decrease in the amount of pufling, In gen- eral, the plats picked later were a little slower in developing because of uneven seedling growth before setting in the field. I00 .90 8O F/PS T : ssco/vo P/CK/NGS P/CK/NGS <73 O (a PEP CENT PUFF c» 4t o o 8 N UVCHES zQA/NFALL 2O /0 / 5 /0 15 20 25 30 4 MAY 1.935 JUNE (Dares of Ra/‘nfafl/ 5 U10 J5‘ 20"‘ 25". 30ml 5 U/ollm/s ‘ 20 JUNE L935 JULY (Dares of Securing Puff Records) Figure 3. Comparison of rainfall at about the time of fruit setting with per cent of puff at harvest. Marglobe No. 434. College Station, 1935. Greater variation was found among lots at the second picking. For the plats picked first from June 11 to 17 there was a marked reduction at the second picking. For those picked after June 25, which already had a reduced amount of puff, there was less difference or none at all between the two harvest periods. Lot 414, a selection of a varietal cross, was grown in four adjacent plats during the same season. Data were taken on plats 4A and 7A on June 11 and 13 respectively, on plats 5A and 6A on June 29 (Table 51). Percentages of puff for the former are 24 and 27 and for the latter 7.1 and 7.2. These four plantings were set the same day and developed equally. It was the original intention to secure data only from 4A and 7A; for this reason, pufling data were not obtained for the early fruits of 5A and 6A. This explains the lower number of pufied fruits for these lots. Fruits from all four plats were examined on Julry 12. The relative percentages of puff were reversed at this time. Those lots whose fruits developed over the same period had about the same amount of pufiing. 23 FACTORS AFFECTING THE AMOUNT OF PUFFING IN TOMATOES 003E008 00000Hmc00 0H0 QMOHHH .3 0 00 0035?... . . . . . . . . . . . . .. 0H 0 u w I: : H HQH 00H I: 05% m0 w0m ...............0n0HU .--- - -. - .1. Q N -.N.w I Q ..W --..----UQQ~O . H6 0 H. m ..0H : 0 HH 0: :3 : 00H m? .......E30m~0.:oHm .1 . . . . 0v . . H 0w mm I: : m h h IHH 05;. 000 0 3a 0Q 0N 0 0 mm I: : H 0 Hum I: : d: 0mm ........:0.S0O >000 I. 00H 50 Nu 0 mm mom I: : m m0 m2 ..0H 003.- <0 m2 IQBHBQ 2am w». 0 H 0 I: : 0 mH 0N 1m 33.. m: 000 ............:0c0Hi0M I. >00 0H N». 0 > m0 ImH : H. 0: N8 : 0:: w <2 m? .............§§=Sm 0 5.0 0.0 5H. 0 N w». I: : 0 0H Ho: ..H“ 30H m2 03. .............0=0HH._mM 0 00H 0.0 w.» 0 w 2 I: : 0 3 “mm . .~ 33. QNH 0H0 . 003E050 “HQBQ l. ~10: 0.0 0w 0 0H “um I: : m 0w 5w ..0H : 40H 2+ . . 520E000 EQEQ || 2 Q 0H 2 0 0: mm ..0H : u 0H 0H. 10w : 0w $0 . . 020E000 082a 1| 0.2 H .0 3 0 m w: ..0H : 0 m0 00H :3 003. m“ 0mm . . 520E000 0003C 0 N0 .0 mm wH 0 0H m». ImH : H 0m o: . .0 30H. m0 $0 . . 520E930 $53G 0 m0. w 0.0 m: 0 m Q ..0H : H 0m u: 1% : U: 8H. . . ($500M 00030H0Q 0 00H mm N0 0 I. mm I: : 0H HQ m». I: : 0§E80m 0.00.20 . . .~ . . . . . ._ .-... Q W O I Q ..© I .-......~m—h.Nmw.v=d£U . .. .. ... ... Q Q I a ..M, ~A:J¢Q.. -.....-.....~.~.N..HU.NU.®U 0 C10 Nw E 0 00 Na I: : m 00 3 I: : 40H +3. ..............H0EEH._m 0 ~50 Nm 0n u 0m >~H ..0H : m 0o 00H ..:~ 05;. <: N2. .........>mQ.O V0005 0 m0; 2 2 0 R 00H ..0H : m .2 3N I: 05;. <0: 00H. .......;8m >E8m . . 2 0 m N I: : a >0 m3 I0 30h m» N: ........0m0m 550m - ...... ...... ..... Q Q I a I .. .....umUm>CCOm + 00.0 m» Na H NH“ 0w ..0H : H. >0 0- INN : m». N2 1.1080 >==om I 00H 0H 0m 0 hm m2 I: : w 0o m3 .HH 05;. <0 02 .....30m 200cm »-....-. .-.... ....- Q a Q ..Bfi I Q ..@ .0...» -U@.N@mEoO@m + 00$ w». 0N 0 3 0w ..0H : N w» 00H 0m : m0 rm. . . . . . . 000000505 0 m“ . N 0w i. w 00H 3. . ,~H : 0H 00H on I: 05;. <~H. 00w . . . . . . . . 1800000 .| 2.0 0H 2 0 NH 0.0 ..0H : H mm wHH ..H 23 00H us. ......$:00m 0 00H mm 0H. 0 a 0N ..0H : u 00H w0H .3 : m2 0% ................=0>< 0 0000.0 HH ~H 0 m 2. ..0H 33. m 2. 0mm .3 05;. U: 5% .. .............0HH0H< 000>0w .0oH>H 000>0w .002 000000 0cou0w 02E H0500: c0030 H0500 c0013 E0 || .02 000G .02 000D =03 .02 098:0 0o 000:0 .02 000:0 .02 000A 00A >00€0> *w0:H0> 000:0 0000 00m 00000 0c000m 00000 00th .00:.~0i 10:0 .80 25am 130w :0 Uomflmn Ewan 5233M 9M0=0O|wi0EfiQH0> 0U 35am a6 m-Qqhufi “vii M030??? uQ ién-uflfi-HOQ fin 01nd? 24 BULLETIN NO. 541, TEXAS AGRICULTURAL EXPERIMENT STATION 0 H00.0 0H HH 0 0 00 ..0H : H H0 000 0N : 00H 000 ...............mm00u5w 0 00.H 00 N0 0 NH 0H ..NH : 0 00 H0 .0N : nHOH 000 ..... . . . .5305 001000 I 0.NH 00 00 N HHH 00H ..NH : 0N 00 00 ..HH 055H. 4H 000 . . . . . . . . . . . . 180055 .l 00.0 0.N 0N 0 0 00 ..0H z N 00 0NH .H : m0H 000 . . . . . . . . ..0H05nH H0>o~H . .. . . . . . . . . . . . . . . 00 0 0 HN ..0H : H 00 N0 .N 31 DH N00 .......3500m 2050M 0 0H .0 00 0N 0 NH 0N ..0H : N N0 00 ..0N 0550 UHH 000 . . . . . . . . . . . 2500M 00M . . . . .. 0N 0 N 0H ..NH : H 00 0HH .0 350 mHmH 000 . . . . . . .......H0>H~H 00M .| 0.00 0.0 H0 0 0 H0 .NH : N HNH 00H .NN : mHwH N00 . ......H5050HH#H .|. 0.0H 0.0 00 N 0H N00 . .0H : NN 00H 000 .0N 055H. m0H 000 . .. . . . . . . . . 050005500 0 0.0 0.0 0 0 0NH ..NH : 0 0 00H ..0 : mNH 000 . . . . .............55H~H 0 0N.H N.0 0.0 0 0 H0 ..NH : 0 00 NNO ..H : 00H 000 . . . . ......50HH05H 500m 1...... . . . . . . . . . . . 0H 0 H 0H ..NH : 0 00 00H I0 : mHOH 000 1-000% 05502205500 0 00.N 0 H 0.0 0 N 00H .NH : 0 N 00H I0 35H. 50H 000 ................5000m . 00 . . . . . . . . .. . 0H 00 0 ..0N 055H. m0H 000 ..............050055O 0 000.0 00 00 0 0N H0 ..0H : H 00 00 ..N : ON 000 . . . . . . . . . . .. . 05052 NN 0 0 0H ..NH : 0H NN 0H I0 35H. moH N00 . . . . . . . . . . . . . ..O.H>H 0N 0 0 w ..0H : H 00 NNH ..0N 055H. U0 00N . . . . . . . . ..E5580H>H 0 0NN.0 0H NH 0 0H N0 ..NH : H 00 NOH ..H 35H. O0H 000 . . . . .. .. 000E802 0 000.0 0H 0H 0 0 N0 ..0H : H H0 0NN ..0N 055H. m0H H00 .50000:50H>H .. N0 0 N 0H ..0H : 0 00 00 ..N 35H. D0 000 .............05o_0§2 .. 00 0 0H N ..0H : H N0 N0 ..0N 055H. m0 000 .............0noHw._0H>H 0 N00.0 N0 00 0 H0 0N ..NH : 0 HHH HOH ..0 35H m0 H00 .............0noHw50H>H 1| 0.0H HN 00 0 00 0HH ..0H : 0H HOH 00N .NN 055H. m2 000 .... . . . 55TH 050HmH5oH 0 00.N 0.N 0H 0 0 00 ..NH : 0 HN 00H Z0 : O0H 000 . . . . 10505.0 050525 0.0 HN 0 0 N0 .NH : 0 0N 000 I0 : m0 000 . . . . 2.105050% 052A .. 0H 0 H 0 .NH : H 0N 0HN I0 350 mHNH 000 . . . . . . . . . 1.5505503 .| 0.0H 0.0 NH 0 H w: ..0H : N H0 000 .NN : m0H 000 . . . . . .. ......05o50vH .| 0.NH 0.0 00 0 N 00 ..0H : H 00 00H .HN 055H. <0H 000 . . . . . . .... 155E 055H. .. . .. 0.N 0 H 0 .NH : 0 HN 0NN H 3i QOH H00 ..........500m55oH. 0 000.0 0H HH 0 0 NN .NH : H 00 00N .NN : mHOH N00 . . . . . . . .5000 5500 . . . . . . . . . .. H.0 0 H H ..0H : 0 0 00 .0N : m0 000 . . . . .....500m55oH. 0 0N.N N0 0H 0 H 00 ..0H : 0 0 00 ..0N : m0 000 . . . . ......H00m 55oH. .. . . . . . . . . . .. N.N . . . . . . . . .. ..0H : 0 N 0N ..0N 055H. 00 N00 .........500m55o0 . . . . . .. . . NH 0 0 0 ..0H : 0 0 00 ..0 : mH 000 ............500m5HHo0 0 00.0 0.0 HH 0 N N0 NH : 0 0N NON .N : 00H 000 .... $05500: 0:50 :50 . . . . . . . . . . .. HH 0 0 0N ..0H : 0 N0 00N ..N : Q0 N00 .....000H50H>H 00050 :50 . . . . . . . . . .. 0H 0 N N ..0H : 0 NH H0 IN 35H. O0 000 .....H0vH50H>H 880 :5U 0 0H0.0 NH NH H 0H 00H . .NH : N 00 NON NN : m0 000 ... . .500H50H>H 300w :50 . . . . . . . . . . . . . . . .. 0. 0 0 0 0N ..0H : 0 0H 000 .NN : Q0 000 .....000H500HH 800m :50 0 H00.0 H0 H0 0 N0 00 ..0H : 0 0w 00 .NN : Q0 000 2.10520 505050 .|. 00.0 0.0 NH 0 0N 00N . .0H 35H. 0 N0 00N .0N 055H. m0H 000 12250050 50300 050>0m 0oH>H 050>0w .000: 050500 H05o00w 35TH H0555 50:00 H0555 50:00 H50 .02 000D 67H 050D 50S .02 005050 0o 00:50 .0H/H 00:50 .0H/H -0003 00H >00H50> *m05H0.> . 00:50 0500 50m 02505 05o00m 0250a 005E HQH 35am H8000. =0 won-000 m-vfiimwiaOléemuofi £060 600a 5:35am UWQmmODIIIHanQQQnQAJMYVQmu 35am u: 00050.0 05d moHwomuFv u: 5001:9500 .NH Q17»? FACTORS AFFECTING THE AMOUNT OF PUFFING IN TOMATOES 25 The evidence from lot 415 shows the same thing. Data taken 0n 12B on June 22 show twice as much pufiing as data on 7C and 12C taken on June 28. The data for the last four lots (7C, 12C, 3D, 7E), taken over a period of 6 days, are in substantial agreement and differ from data taken only 6 days earlier. A change in environmental factors seems to be a likely explanation. It would seem that records taken on different days may or may not be comparable, depending on the time involved and on the rate of change of environmental factors during the effective period. The very exceptional rainfall of 10.29 inches occurred during May of 1935; then comparatively dry and wet months alternated. Under such circumstances, the result for any period depends upon the proportion of fruits developing under the various conditions which are included. For this reason, examination dates have been given. A comparison of the two periods of Table 17 shows that there was significantly more puff during the second period in but 2 cases, while there was significantly less puff for 16 lots. In addition, all but one of the check plats mentioned above had less puff during the second period. Of the 3O instances in which the change was no greater than might be due to chance, 17 had less puff the second period. A number of these had a marked reduction during the second period but, as in the case of Avon, it seems likely that chi square was not high because of the small numbers of fruit. Nine others had more puff and 4 showed practically no change. The reduction in pufiing presumably reflects the difference in available moisture between May and June. 50 45 3 40 6 J5 7 \ LL 4 ‘E25 5% y. ‘g E15 3g \ Q 0 . 027 1 / MAY 1.9.36‘ JUNE Figure 4. Per cent of puff among fruits set during periods indicated by horizontal lines, showing effect of rainfall at time of setting on per cent of puffed fruits. All varieties. College Station, 1936. Dotted line indicates few fruits set. 26 BULLETIN NO. 541, TEXAS AGRICULTURAL EXPERIMENT STATION During the 1936 season at College Station several thousand flowers were tagged with the date of opening, and when examined the fruits were classified according to age. This permits a fairly exact examination of the effect of rainfall during the period the fruits were setting on the proportion of puff among these fruits when harvested. This comparison is made in Figure 4. Per cent of puff is represented by a straight line determined by the average of all lots for the period. Very few fruits were set during the latter part of June because of the high temperature and low humidity. This is indicated by the dotted line. In each case the pro- portion of puffed fruits is seen to be influenced by the soil moisture during the period of fruit setting. The data on which Figure 4 is based are presented in Table 18. The proportion of severely puffed fruit seems to change more with a change in moisture conditions this season than that of those moderately puffed. In the period from May 13 to 19 the severely puffed fruit make up only Table 18. Pufling compared with rainfall during fruit setting—College Sta- tion, 1936. Based on total fruit harvested—-all varieties. Number of fruit Per cent puff Date of fruit Rainfall setting (inches) Normal Moderate Severe Severe Total Before May 7 . . . . . . . . . . . . . . 538 133 42 5.9 24 2.751 May 7 to 12 . . . . . . . . . . . . . .. 1172 331 99 6.2 26 2.50 May 13 to 19 . . . . . . . . . . . . . . 2694 S16 57 1.7 18 0.29 May 20 to JuneS . . . . . . . . .. 2022 1160 317 9.1 42 5.09 After June 8 . . . . . . . . . . . . . .. 133 77 49 19 49 14.102 1From April 21 to May 6. 2T0 July 16. 10 per ce'nt of those puffed, while during the last period they form nearly’ 40 per cent of the total puffed. The last period has a duration of over 5 weeks and it is impossible to determine the exact proportion of fruit setting during the earlier, drier portion. It is known that considerably more set after the rains began than before. In Table 19 may be found the individual variety records secured at College Station during 1936. In 3 instances there is a smaller amount of puff during the second period and in 1O cases a larger amount. All three of the former (Ailsa Craig, Beauty of Lorain, and Tuckswood) have relatively small fruits with a higher production during the dry period of late June than the other varieties. Discussion: Aside from the fact that a growing plant confined as to soil supply is continually changing its conditions of growth as it develops, the available moisture is considerably more uniform in the greenhouse than in the field. This advantage is somewhat reduced by the smaller amount of data obtained. For the two varieties used, the second and third greenhouse experiments point definitely toward an increase in puff with increased available moisture during periods when high temperature is not the dominant factor. FACTORS AFFECTING THE AMOUNT OF PUFFING IN TOMATOES 27 Results from differential irrigations in the field are evidently compli- cated by a number of factors. When differences in available moisture in the field due to differential irrigation or periods of rainfall are considered, it is found that the different varieties and sometimes difierent strains of the same variety do not respond the same. Where a change in the amount Table 19. Comparison of varieties and periods of fruit development, College Station, 1936. Based on total fruit for each period. No. of fruits Per cent puffed Variety Lot __§__ No. Set April 21 to June 20 Set June 20 to July 16 First Second Denod period Normal Mod. Severe Normal Mod. Severe Ailsa Craig . . . . . . . . . . . 515 68 14 10 33 0 0 26 0 Alice Roosevelt . . . . . . . . 516 45 3 0 18 8 1 6.2 . . . . . , , Beauty of Lorain . . . . . . 520 29 23 5 28 8 3 49 23 Blue Star Beauty . . . . . . 534 17 5 2 18 1O 8 . . . . . . . 50 Bonny Best . . . . . . . . . . . 524 32 7 2 13 . 3 2 22 . . . . . . . Bonny Best . . . . . . . . . . . 525 17 15 2 8 1 1 50 , _ , , _ _ _ Bonny Best . . . . . . . . . . . 531 26 8 1 7 8 0 26 , , , _ _ _ _ Bonny Best . . . . . . . . . . . 710 32 2 0 11 3 2 5.9 . . . . . , _ Break O'Day . . . . . . . . . . 492 67 17 2 20 18 7 22 55 Break O'Day . . . . . . . . . . 536 27 7 1 8 8 1 23 _ _ _ _ _ _ _ Canadian . . . . . . . . . . . . . 540 47 10 1 1O 1 0 10 _ _ _ _ _ _ _ Chalk’s Jewel . . . . . . . . . S43 25 2 4 5 3 2 19 , _ _ _ _ _ _ Clark's Early . . . . . . . .. 541 30 4 1 7 2 o 14 _ _ _ _ _ __ Clark's Early . . . . . . . . . 542 32 9 O 9 5 0 22 _ _ _ _ _ _ _ Clark's Early . . . . . . . . . 711 39 11 0 11 7 4 22 . . . . . . . Danish Early . . . . . . . . . 548 93 8 6 '24 10 17 13 53 Dwarf Early Red . . . . . . 555 16 13 33 8 5 10 74 _ _ _ , _ _ _ Earliana . . . . . . . . . . . . . . 440 44 4 0 5 1 0 8. 3 . . . . . . . Earliana . . . . . . . . . . . . . . 453 24 8 3 1 2 0 31 . . . . . . _ Earliana . . . . . . . . . . . . . . 557 36 12 2 2 5 0 28 _ _ _ _ _ _ Early Detroit . . . . . . . . . 560 15 2 1 18 12 6 . . . . . . . 50 Early Texas Special. . . . 562 12 14 8 6 12 7 65 _ _ , _ _ _ _ Ficarazzi . . . . . . . . . . . . . 563 34 5 0 8 9 1 13 _ _ _ _ _ _ _ First Early . . . . . . . . . .. 718 38 10 0 . . . . . . . . . . . . . . . . . . . .. 21 . . . . . .. Globe . . . . . . . . . . . . . . . . 571 22 11 O 5 13 2 33 _ _ _ _ _ __ Glovel . . . . . . . . . . . . . . . 574 38 11 1 22 18 2 24 43 Greater Baltimore . . . . . 576 26 8 1 5 3 1 74 _ _ _ _ _ _ _ Grothen Globe . . . . . . . . 579 24 13 1 12 10 4 63 , _ _ _ _ _ _ John Baer . . . . . . . . . . .. 359 24 9 0 14 10 3 27 _ _ _ _ _ __ John Baer . . . . . . . . . . . . 457 33 8 0 10 0 2 20 _ _ _ _ _ _ _ John Baer . . . . . . . . . . . . 595 47 6 0 8 8 3 11 , , _ _ _ _ _ Kanora . . . . . . . . . . . . . . . 597 46 4 O 28 12 1 8 32 King Humbert . . . . . . . . 599 35 6 4 6 4 O 22 , _ _ _ _ _ _ Kondine . . . . . . . . . . . . . . 600 58 7 1 17 3 0 12 , _ _ _ _ _ _ Large Red . . . . . . . . . . . . 605 26 18 6 11 13 4 48 . . . . . . . Lucullus . . . . . . . . . . . . . . 611 35 7 0 41 1 17 13 Marglobe . . . . . . . . . . . . . 434 502 195 25 272 357 51 30 60 Marglobe . . . . . . . . . . . . . 624 26 12 0 20 10 0 32 33 Marglobe . . . . . . . . . . . . . 625 19 1 1 3 21 13 1 42 40 Marglobe . . . . . . . . . . . . . 626 29 10 2 8 7 O 29 . . . . . . , Marglobe . . . . . . . . . . . . . 708 33 12 3 24 30 4 31 59 Marketeer . . . . . . . . . . . . 631 3O 3 0 15 2 0 9, 1 _ _ _ _ _ _ _ McGee . . . . . . . . . . . . . . . 635 50 19 1 9 4 O 29 . . . . . . . McGee . . . . . . . . . . . . . . . 636 24 7 2 s 1 o 27 , , , _ _ , _ New Orleans Market. . . 639 33 4 0 6 8 1 11 , _ , _ _ _ _ Pennsylvania State. . . . 644 43 18 0 13 12 1 27 42 Pritchard . . . . . . . . . . . . . 646 20 5 0 2S 18 2 . . . . . . . 44 Pritchard . . . . . . . . . . . . . 647 51 32 2 39 28 9 40 49 Queen of the Earliest. . 651 33 4 1 7 12 2 13 . . . . . . . Royal Purple . . . . . . . . . . 490 15 2 1 25 12 5 . . . . . . . 40 Scarlet Dawn . . . . . . . . . 508 15 1S 1 10 5 2 52 . . . . . . . Stokesdale . . . . . . . . . . . . 709 28 1O O 8 7 0 26 , , _ _ , _ _ Stone . . . . . . . . . . . . . . . . 661 34 1 O 19 5 1 28 . . . . . . . Success . . . . . . . . . . . . . . . 663 39 2 0 13 4 0 4.9 . . . . . . . Sunrise . . . . . . . . . . . . . . . 497 64 19 1 21 7 1 24 . . . . . . . Sunrise . . . . . . . . . . . . . . . 664 47 16 0 16 8 3 2S . _ , _ _ , _ The Trophy . . . . . . . . . . . 666 56 7 7 15 11 7 20 55 Tuckswood . . . . . . . . . . . 667 58 8 5 46 9 0 18 16 Westlandia . . . . . . . . . . . 668 88 19 A3 48 6 1 2O 13 28 BULLETIN NO. 541, TEXAS AGRICULTURAL EXPERIMENTCSTATION of puff occurs it is usually in the direction of the moisture change. Cooper’s Special and Gulf State Market did not respond to differential irrigation treatments. Marglobe gave the greatest response; Chalk’s Jewel, Pritchard, Scarlet Dawn, and Rutgers gave less. Table 20 shows the behavior of varieties for which there are results for several lots over a period of years. In only 2 cases out of 110 was the response in a direction opposite what is expected——that is, less puff with Table 20. Response to changes in rainfall-{Jollege Station, 1931-1936. Number of lots. Change as expected Change Variety No change opposite to Not expected significant Significant Bonny Best . . . . . . . . . . . . . . . . . . . . . 3 4 S 1 Break O'Day . . . . . . . . . . . . . . . . . . . 1 1 6 l(?) Cooper’s Special . . . . . . . . . . . . . . . . . O 0 4 0 Dwarf Champion . . . . . . . . . . . . . . . . 1 3 5 0 Earliana . . . . . . . . . . . . . . . . . . . . . . . 2 3 5 0 Early Detroit . . . . . . . . . . . . . . . . . . 1 2 3 0 Globe . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1 5 0 Gulf State Market . . . . . . . . . . . . . . . l 1 ll 0 John Baer . . . . . . . . . . . . . . . . . . . . . . 1 2 l 0 Marglobe . . . . . . . . . . . . . . . . . . . . . . . 7 8 2O 0 Total . . . . . . . . . . . . . . . . . . . . 18 25 65 2 more rainfall. Since the conditions under which these fruit set are known only approximately, it is possible that, if the exact moisture conditions were known, these results would fall into line. Lack of significance in the change may be due in some cases to small numbers of fruit. A tendency was noted for certain lots both in the greenhouse and under irrigation in the field to show differences in pufling under differential treatment early in the fruiting period but not later. The development of the root system is no doubt a factor here, as perhaps are changes in struc- ture of the stem and leaves. Possibly the best evidence of a direct general relationship between the amount of available moisture and the amount of puffing comes from a comparison of results secured in the field over several periods. With the exception of the very hot 1934 season there was a general decrease in the amount of pufling with the advent of the drier part of the season. What is perhaps more important, during the season (1933) in which the wet and dry order Was reversed there was a general increase in amount of puff. Further, the effective period has been found to be during setting and early development of the fruit. Evidence for this comes from both greenhouse and field. The preliminary results with sprays and possibly the results with ferti- lizers, discussed later, give an indication that a number of factors influencing proportion of fruits puffed may be effective through their influence upon water conditions within the plant. Thus one group of fac- tors, such as rainfall and irrigation, soil type, and temperature, seem to 1, ., am-pr-a» ,-, .. FACTORS AFFECTING THE AMOUNT OF PUFFING IN TOMATOES 29 exert an influence because 0f their effect on available soil moisture; an- other group, such as humidity, temperature, and sprays which have a bearing on rate of transpiration, may be effective in this way; and a third group, such as fertilizers which have an effect on the amount of plant colloids, may in this way affect water conditions within the plant. It is possible also that varietal differences may be of the latter type. Only very brief mention of the work of the United States Department of Agriculture (1) along this line is yet available. On page 14 of the “Report of the Chief of the Bureau of Plant Industry, 1935” we find the follow- ing paragraph: “Physiological studies have shown that one of the primary causes of pufiiness in tomatoes is unfavorable water conditions, while other factors that may affect ovule fertilization also plays an important part. Main- tenance of a uniform and adequate water supply and avoidance of low temperatures prevent the trouble in large measure.” While this indicates results somewhat different from those reported here, full agreement could hardly be expected where results vary so widely and conditions are difficult to control. Varietal or even strain differences could easily account for large discrepancies between results of independent workers. It is possible that there are one or more con- tributing factors that have not as yet been taken into account. Temperature The results secured in the greenhouse during the late spring of 1935 did not show a significant difference between plants growing in the tile under different moisture conditions. Those plants with a low “Water table” had a slightly higher percentage of puff than those with a high water table. The data arranged according to harvest periods are pre- sented in Table 21. It will be seen from Figure 5 that when these results are arranged according to time of setting the fruit, there is a general agreement in trend. First there is a reduction in the amount of puff, then an increase to about what it was before, then a second decrease, and finally a fairly consistent rise to 100 per cent or thereabouts. Table 21. Diiferential water treatrnents—spriing 1935. Based 0n total fruits each period. Ten-inch pots Low water table High water table Period No. No. Per cent No. No. Per cent No. No. Per cent; normal puffed puffed normal puffed pufied normal puffed puffed May 9 — 15 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 22 82 " 16 - 2o 6 11 6s 10 14 5s 6 37 s6 " 21 — 25 8 2 2O 2 14 88 14 21 60 " 26 — 31 13 2 13 9 48 84 13 46 78 June 1— 5 5 11 69 8 26 77 15 40 73 " 6 - 10 4 s o7 4 37 90 12 16 57 " 11 — 15 1 6 86 2 18 90 9 17 65 " 16 — 20 2 7 78 1 31 97 1 43 98 " 21- 27 0 3 100 0 6 100 o 16 100 " 30. . . . . 4 20 83 0 16 100 4 54 93 30 BULLETIN NO. 541, TEXAS AGRICULTURAL EXPERIMENT STATION 10o - .95 - 90- 3 3 d S‘ & 0s Q $8‘. / KEY I — — — — Ten —inch Pars‘ 4o _ \ / ——— — Low Wafer Table / —-i- High Wafer- Tab/e PER CENT PUFF {x b1 % i 15» \\J 10-........ . 1e ' .20 24 2a 1 5 s 13 1r 21 2s. 2s. .MAY L935 JUNE Figure 5. Pufling percentages, gr§enhouse——data arranged according to time ruit set. Q Ul PEP CENT PUFF m lb Ul O M O Per C enr Puff- H/yh Wafer Tab/e '-'—-—- Max/mum Green/muse Emperarures -—--—M1nimum Greenhouse Temperatures i--—- Mean Oufside Emperarures U! Q i DEGREES FAHPENHE/T KM U! 2 s 1a 4 1a 22 2e a0 a 7 1 1 1s MAV / 93 5 JUNE DA T55 0F TEMPERA TURE RECORDS 1s 2o 24 2a 1 5 s 1.3 17 21 25 2.9 MAY JUNE DATES 01- SECUR/Al/gas/PL/FF RECORDS Figure 6. Comparison of percentage of puffing in greenhouse With tem- peratures at time fruit is setting. The horizontal lines represent the harvest period on which the per cent of puff is based. FACTORS AFFECTING TIIE AMOUNT OF PUFFING IN TOMATOES 31 When the results for the high water table lot are compared with daily maximum and minimum greenhouse temperatures and with the daily mean outside temperature at the time the fruit is setting (Figure 6), we find a similarity between the puffing curve and the minimum greenhouse and mean outside temperatures up to the Phint where the maximum greenhouse temperature exceeds 100°F. From May 7 to June 1 the correlation between the per cent of puff and mean outside temperature is .34. When the maximum greenhouse temperatureexceeds 100° the percentage of puffed fruits rises immediately to 95 or more. As soon as the maximum temperature fell below 100° the percentage of puffed fruits decreased. The finely dotted portion of the maximum greenhouse temperature line represents an estimate based on the mean outside tem- perature for June 2. Table 22. Temperature data for College Station Temperature (degrees F.) 1931 1932 1933 1934 1935 1936 March (mean max.) . . . . . . . . 67.2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (mean min.) . . . . . . .. 43.2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. (mean mean) . . . . . . . 55 . 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . April (mean max.) . . . . . . .. 75.0 81 3 81.2 81.2 79.1 80.7 (mean min.) . . . . . . .. 51.6 57 4 56.2 59.4 59.2 53.0 (mean mean) . . . . . . . 63.3 69 3 68.7 70.3 69.2 66.8 May (mean max.) . . . . . . . . 82.7 86.1 89.8 87.6 83.0 83.4 (mean min.) . . . . . . . . 59.3 64.0 67.8 62.4 64.5 64.6 (mean mean) . . . . . .. 71.0 75.1 78.8 74.9 73.8 74.0 June (mean max.) . . . . . . .. 94.6 92 3 93.2 98.3 90.0 95.0 (mean min.) . . . . . . .. 69.7 72 5 66.8 71.5 71.1 71.2 (mean mean) . . . . . . . 82.2 82.4 80.0 84.9 80.6 83.1 July (mean max.) . . . . . . .. 96.2 98.5 96.2 100.8 94.3 91.2 (mean min.) . . . . . . .. 72.8 74.0 73.8 73.6 73.6 72.5 (mean mean) . . . . . .. 84.5 86.3 85.0 87.2 84.0 81.9 August (mean max.) . . . . . . .. 96.2 96.6 95.1 98.6 96.9 96.0 (mean min.) . . . . . . .. 69.5 73.7 72.3 73.7 72.8 72.2 (mean mean) . . . . . .. 82.9 85.2 83.7 86.2 84.9 84.1 of high temperature is not obtained in the College Station covering the period of the in Table 22. The mean maximum tempera- From July 3 to 28 Usually this drastic effect field. Temperature data for experiments are to be found ture for the entire month of July 1934 was 100.8°. inclusive there were 13 days with a maximum temperature of 100° or. over. The highest temperature (108°) was reached on Jully 24. While fruit setting was light during this period, the percentage of puff was high as compared with that of fruits set the following autumn (Table 15). This high proportion of puff during the summer is considered to be due to the high maximum temperatures at this time. No other season had such high maximum temperatures and for this reason high temperature rather than available water is considered to have been the dominant environmental factor. There has been no opportunity to study unfavorably low temperatures. It is possible that the relatively low temperatures of March 1931 con- tributed to the puffing of the earliest fruits harvested that year. 32 BULLETIN NO. 541, TEXAS AGRICULTURAL EXPERIMENT STATION Soil Since the amount of available moisture is an important factor in de- termining the proportion of puffed fruits, different results may be ex- pected from the same lot of tomatoes grown on different soils. In addi- tion, other factors, such as differences in fertility, in organic matter, and in the available minor elements, may have an influence. The degree of effect of slight soil differences is important in a comparison between field grown plats differing with respect to some cultural treatment or genetic factor. The replicated plantings of Marglobe made in 1935 serve as a measure of the variability due to soil heterogeneity at College Station (Table 16). Comparisons of replicated plats for the same period eliminate differences due to rainfall. The values of chi square presented in Table 23 are for Table 23. Comparison of replications of Mal-globe 434-—College Station, 1935. (Data presented in Table 16.) 1 1 Values of chi squarc* Lots compared "~— First picking Second picking 2A- 8A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0.470 9.18 2A-14A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0.136 17.2 8A-14A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 1.36 57.3 2A- 5B . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 3.94 0.72 2A- 8C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 2.4 13.2 2A-11D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0 263 28.3 2A-14E . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . O O07 15 8 8A- 5B . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 1.24 4.71 8A- 8C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0.94 0 75 8A-11D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 1.47 10 8 8A-14E . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0.275 1 98 14A- 5B . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 5.14 30.1 14A- 8C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 4.22 65.1 14A-11D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0.043 72.3 14A-14E . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0.053 25.8 11B-14C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 10.2 . . . . .. 11B-17D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 2.03 . . . . .. 11B- 2E . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 4.93 . . . . . . 11B- 8E . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 3.88 . . . . . . 11B- 5F . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0.005 . . . . .. 11B-11F . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0.176 . . . . .. 17B- 2C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 1.1 12.2 17B- 5D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0.067 0.20 2E- 8E . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.079 . . . . .. 2E- 5F . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 5.12 1.25 SF-11F . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0.316 . . . . .. * Values of 5 or more are considered significant. the same period except in the case of 11B-14C, which gave a highly sig- nificant difference. The plants were grown on Lufkin fine sandy loam. The A plats are ranged across one end of the field and the F plats across the other, with the rest arranged alphabetically between as previously described, The end of the field in which the F plats were located seems to be a little FKXUIORS AFFECTING THE AMOUNT OF PUFFING IN TOMATOES 33 heavier than the rest of the field. For the first pickingithere are only two cases in which the difference between plats is probably significant (14A-5B and 2E-5F). Since each of these pairs is in the same end of the field, and comparisons of similar plats do not show a significant differ- ence, it is not thought that this represents a soil difference. The difference between 11B and 2E may be due to this factor. When the second picking is considered, wide variations are found for two-thirds of the comparisons which have sufiicient data. The heavy clay subsoil has a very definite undulating surface, causing the overlying sandy layer to vary from 5 or 6 inches to as much as a foot or more in depth. As the plants develop, available water supply would thus vary consider- ably between the replications and this is probably an important factor con- tributing to the differences observed later in the season. The data for the replicated plantings at College Station have been dis- cussed elsewhere (25). The percentages for these varieties—Albino, Kanora, and Marglobe—are included in Table 14, and the chi square cal- culations are given in Table 24. The tomatoes were grown on two pieces Table 24. Comparison of replications—College Station, 1933. Values of chi square* Variety Lot Plats No. compared June July Albino . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 194 3C—15 0.413 2 .04 Kanora . . . . . . . . . . . . . . . . . . . . . . . . . . .. 26 l6A—19 1.12 20.3 Llarglobe . . . . . . . . . . . . . . . . . . . . . . . . . . 40 3C—12C . . . . . . 0.152 Marglobe . . . . . . . . . . . . . . . . . . . . . . . . . . 40 3C—19C . . . . . . 2.39 Marglobe . . . . . . . . . . . . . . . . . . . . . . . . .. 40 3C-19 . . . . . . 0.148 Marglobe . . . . . . . . . . . . . . . . . . . . . . . . . .. 40 12C~19C 0.031 0.240 Marglobe . . . . . . . . . . . . . . . . . . . . . . . . . .. 40 12C—l9 1.67 1.28 Marglobe . . . . . . . . . . . . . . . . . . . . . . . . . . 40 19C—19 2.34 5.25 *Values of 5 or more are considered significant. of ground about 4 rods apart that season (1933). The plats of one plant- ing were both numbered and lettered; the others were given a number only. The harvests are grouped according to the month they were secured, the exact date not being recorded. There were no significant differences between replicated plats for the first picking. As in 1935, some of the plats, in this case 2 outof 8, had a significant difference later in the season. Calculations were not made for comparisons involving Marglobe plat 3C for the first picking because of small numbers of fruits. Results of replicated plantings of Marglobe for the 1930 season at Weslaco are included in Table 43. Plants were grown in single row plats ' extending across the narrow way of a rectangular piece of ground. The plat number coincides with the row number, which gives an indication of distance between plats. The test was on Filigonio fine sandy loam soil. The comparisons for these plantings are given in Table 25. There is general agreement among the different plats. The two exceptions in- volve the middle and one border plat, one having significantly more, the other less, puff. The evidence from both locations indicates that where 34 BULLETIN NO. 541, TEXAS AGRICULT.URAL EXPERIMENT STATION Table 25. Comparison of Marglobe plantings-—\Veslac0, 1930. \/alues of* Plats compared chi square 1- 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1. 15 3— 9 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 . 14 3-11 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0.053 3-13 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 1.80 3—15 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 5.67 3-17 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 2.76 3-19 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0.058 3-21 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 1.56 3-23 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0.578 3-25 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0.0 3-27 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4. 62 9-11 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0.707 9-21 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0.02 9-27 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 1.22 23-25 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0.578 23-27 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 8.14 25-27 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 4.62 * Values of 5 or more are considered significant. the soil is reasonably uniform this is not likely to be an important factor for small areas, especially earlier in the harvest season. A restriction of comparisons to plats in adjoining rows would be expected to reduce later variability due to soil heterogeneity. The possibility that the lack of pufling in the North might be due to some minor element in the glacial soils of that area led to a comparison of plants grown in pots in soil from Ann Arbor, Michigan, with plants grown in Texas soil. Five plants were grown in each soil in 10-inch pots in the greenhouse during the winter of 1935-36. While few fruits were obtained (Texas soil—5 normal and 11 pufied or 67%; Michigan soil— 7 normal and 14 pufied, also 67%), it is evident that the soil obtained from Michigan does not contain a specific remedy for puffinessfof tomatoes. Fertilizers At College Station, investigation of commercial fertilizers has been confined to a comparison of the effect on puffing in Marglobe and Norton of a 6-12-6 fertilizer at the rates of 300, 600, 1200, and 1800 pounds per acre. These treatments are available for comparison among themselves Table 26. Effect of difierent amounts of 6-12-6 on proportion of fruits puflfeub-College Station. Per cent puffed Treatment (lbs. per acre) . 19311 19321 19331 19343 None . . . . . . . . . . . . . . . . . . . . . . . . . . 33 77 52 58 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 72 41 38 600 . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 60 35 47 1200 . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 66 42 27 1800 . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 66 44 46 Manure . . . . . . . . . . . . . . . . . . . . . . . x . . . 38 1 Marglobe 2 Norton Wilt-resistant FACTORS AFFECTING THE AMOUNT OF PUFFING IN TOMATOES 35 Table 27. Comparison of fertilizer treatments--C0llege Station. Based on total fruits for the season. __ Values of Rates compared Year chi square* None -— 1931 0.522 None —- 1931 5.36 None —— 1931 31.5 300 —— 1931 2.72 600 —— 1931 7.33 1200 —- 1931 0.339 - None —- 1932 3.42 None -— 1932 40.2 None —- 1932 34.7 300 — 1932 2.18 None — 1933 23.6 None —, 1933 42.7 None —-— . 1934 2.99 None —- Manure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 1934 3.70 * Values of 5 or more are considered significant. and with plats receiving no fertilizer (26). All plants were of the same age and were handled alike. Marglobe seedlings were used the first three seasons, Norton cuttings the last season. A manure treatment was added in 1934. The results secured over four seasons are presented in Table 26. In every instance the plants receiving fertilizer had less puff than those unfertilized, The differencebetween treated and untreated plats is not significant in everry case when considered alone, but is always in the same direction. The values of chi square calculated for certain comparisons can be found in Table 27. The difference between plats receiving no fertilizer and those fertilized with 6-12-6 at the rate of 300 pounds per acre is significant only during 1933, but the difference between unfertil- ized plats and those fertilized at the 600 pound rate is significant each year except 1934, when the number of fruits is so small that no single difference is greater than that due to chance. The proportion of puffed fruit has been determined for plats receiving a rather wide variety of fertilizer treatments at the Lower Rio Grande Valley Station for eight different seasons. These treatments are listed in Tables 28 to 32. Seven varieties were used at one time or another. Re- sults for the first five seasons have been considered briefly by Friend (6). His conclusion that fertilizer applications do not affect the amount and degree of puffing under Lower Rio Grande Valley conditions is not modi- fied by the additional data presented here. For certain years, less puff has been obtained with certain treatments than with no fertilizer, but the results are not consistent. A comparison of results with the same variety on successive years discloses as great inconsistency as Where different varieties have been used. When plats receiving nitrogen in some form are compared with those receiving no nitrogen, similar inconsistencies are observed. During 1926 nine plats receiving nitrogen averaged 59.6 per cent puff while six plats receiving no nitrogen in the treatment averaged 62.3 per cent. An average of the five seasons where the treatments were repeated (Table 29) gives 36 BULLETIN NO. 541, TEXAS AGRICULTURAL EXPERIMENT STATION Table 28. Effect 0f fertilizers on pufling of Gl0be—-Weslac0, spring 1926. Based 0n 100 fruits per plat. Plat Rate per acre Per cent No. Treatment (lbs) pu 1 None . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60 7 None . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 14 None . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84 15 None . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60 Average . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64 6 Acid phosphate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 300 76 5 Acid phosphate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 300 I Muriate of potash . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60 42 3 Sulfate of ammonia . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 36 4 Sulfate of ammonia . . . . . . . . . . . . . . _ . . . . . . . . . . . . 50 Acid phosphate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 300 56 10 Cotton seed meal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150 Acid phosphate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 300 60 8 Sulfate of ammonia . . . . . . . . . . . . . . . . . . . . . . . . . . . 5O Muriate of potash . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60 84 . 9 Kainit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 250 52 11 Sulfate of ammonia . . . . . . . . . . . . . . . . . . . . . . . . . . . 85 Acid phosphate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 300 Sulfate of potash . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 72 12 Sulfate of ammonia . . . . . . . . . . . . . . . . . . . . . . . . . . . 8S Acid phosphate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 300 Muriate of potash . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 60 Average . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66 13 Cotton seed meal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100 Sulfate of ammonia . . . . . . . . . . . . . . . . . . . 25 Acid phosphate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 300 Muriate of potash . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60 68 2 Barnyard manure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20,000 48 29.8 per cent where nitrogen was applied and 31.5 per cent for the plats receiving no nitrogen. In both cases there appears to have been an im- provement where a nitrogen carrying fertilizer was used. However, during 1934 plats fertilized with 11-48-0 at the rate of 300 pounds per acre had 64.2 per cent puff compared with 62.7 for the unfertilized plats. During 1936 the plats receiving nitrogen averaged 26.1 per cent against 16.7 per cent for those receiving none. The high amount of puff found among the plats receiving nitrogen alone this wear may possibly be ac- counted for by their position in the field. It will be noted from Table 32 that the other treatments have much less puff and are fairly uniform in this respect. When the four treatments of each replication are averaged we have (following the field arrangement of plats) 14%, 10.5%, 16%, 28%, and for the three forms of nitrogen 49%. Thus when differential treatments are disregarded, excepting the last, there is a consistent in- crease in the amount of puff for each of three succeeding_replications culminating in the high percentages of the nitrogen treatments. Since these latter were not replicated, there is no Way of separating the effect due to position in the field from an effect due to the treatments. The lack of correspondence between these results and those secured during pre- 37 FACTORS AFFECTING THE AMOUNT OF PUFFING 1N TOMATOES kdnrO xmwam m flfiownw wwawQooO N wnosw a 8 fi hm i hN NZ 8 Q Nv Z 2 g w 2 2 oN 9.33 . . . . . . . . .2282 .. .. mm N¢ .. wZ 2 .. .3 .. wN ms NZ .. 3 Z ooo 3 . ........wasaw§ hN “a Nw hm 2 mZ 2 hm hm N; Q NZ wN 3 oN h 8N; .:.:......:.w-w.¢ 3 i wm 2N Zm mN F, Q Q NN on Z 2 Z NZ hN ooc - w .. ¢ .. .. w» Q‘ .. wN 3 .. Q .. wN 3 ZN .. w NN ooo - w é 8 hw n» hm 0N m: w» Q Q Z ZN .3 hN ma 2 NZ 8w - w - w .. .. m» F. .. 2 mm .. 3.. .. oZ ZN w. .. oN NH ooo 47¢ S, fi F, 3. 8 Z an Q s. Z 3 ZN m Z wN u» ooo . . . ...o - w - w .. .. aw mm .. m“ hw .. ma“ .. N; NZ o .. w on ooo . . . . . . . . . . . . . Io-w-w Nm R. $ mm 3 Z H“ w» Nm Z NN NZ 2 mN wN w ooo .... . . . . . . .o - w - o .. .. TN we .. oN mm .. Q .. mN 2 3 .. 3 3 .000 .. . . . . . ...o-w-o s», Q 3 hm NN NN 2 3 NZ“ oN 0N Z NZ mN on NN .... . . .. .. ow mm .. om Nm .. ow .. ZN m; .. .. w 3 .. .. 0m wm .. NZ hm .. Ow .. 0N wN 3 .. wN .. .><. o hN .>< 3 3 $4 Z N .>< oN I wN .>< oN w wmm was». >32 was». wash. was». wash wash ~32 wash. was». Amwasoav IMO>< < awa aawafimwak 3mm “S2 M83 NONOH ~22 shNoZ éméwwa, E5 wulhuwfi coin»? .m:=$aw=aa¢ pwiaiww we Uwafi ioiua-sm own-aw i6 HQ 25am 130w =0 wwomflé 35h no mvwwwflvwnvnm 5N v56? 38 'BULI.ET]N NO. 541, TEXAS AGRICULTURAL EXPERIMENT STATION Table 30. Comparison of fertilized and unfertilized plats of Marglobe-— Weslaco, fall 1934. Based on total harvestable fruit at each picking, the last picking including all fruits of any size. Treatment No. No. Per cent Date of Harvest normal puffed puffed 11 - 48 - 0 300 lbs per A. November 26 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 20 83 December 8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 24 41 December 26 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 199 422 68 Average . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64 Not fertilized November 26 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 46 84 December 8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 52 S9 December 26 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 307 336 45 Average . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63 Table 31. Efieet of fertilizers—Weslaco, fall 1935. Based on total fruit with picking. October 28 November 4 Per cent _ pufi’ Variety Treatment No. fruits No. fruits Normal Mod. Severe Normal Mod. Severe Oct. Nov. Clark's Early. . . . Fertilized*. . 83 10 2 92 7 1 3 18.0 Clark's Early. . . . None . . . . . . 45 2 1 82 2 0 6.3 2.4 Purple Pritchard. Fertilized*.. 49 11 16 198 67 23 36 31 Purple Pritchard. None . . . . . . 42 14 13 235 55 37 39 28 *Each plant fertilized with five ounces of 32% superphosphate applied October 7. Table 32. Effect of fertilizers (Stokesdale), Weslaco, spring 1936. Based on 100 fruit samples per plat. Rate Per cent puff Treatment per A (pounds) Moderate Severe Total Average None . . . . . . . . . . . . . . . . . . . . . . 6 6 12 None . . . . . . . . . . . . . . . . . . . . . . 7 3 10 None . . . . . . . . . . . . . . . . . . . . . . 7 2 9 None . . . . . . . . . . . . . . . . . . . . . . 18 17 35 16.5 0 - 18 - 0 . . . . . . . . . . . . . . . . . . 600 11 3 14 O - 18 - O . . . . . . . . . . . . . . . . . . 600 6 1 7 0 - 18 - 0 . . . . . . . . . . . . . . . . . . 600 2O 3 23 0- 18-0 . . . . . . . . . . . . . . . . . .. 600 7 16 23 16.8 6 - 18 - 0 . . . . . . . . . . . . . . . . . . 400 12 1 13 6 - 18 - 0 . . . . . . . . . . . . . . . . . . 400 12 3 15 6 - 18 - 0 . . . . . . . . . . . . . . . . . . 400 13 1 14 6- 18-0 . . . . . . . . . . . . . . . . .. 400 19 6 25 16.8 6 - 18 - 0 . . . . . . . . . . . . . . . . . . 600 11 7 18 6 - 18'- 0 . . . . . . . . . . . . . . . . . . 600 9 1 10 6 - i8 - 0 . . . . . . . . . . . . . . . . . . 600 16 2 18 6- 18-0 . . . . . . . . . . . . . . . . .. 600 16 12 28 18.5 Sulfate of ammonia . . . . . . . . . 400 18 21 39 39 Nitrate of soda . . . . . . . . . . . . . 500 33 23 56 56 Cyanamid . . . . . . . . . . . . . . . . . 400 35 16 51 S1 FACTORS AFFECTING THE AMOUNT OF PUFFING IN TOMATOES 39 vious years, together with the obvious trend toward increased pufiing in this end of the field, indicate that this wide difference is not primarily due to the nitrogen carriers applied to the last three plats. The application of phosphate alone may have increased the amount of pufling in Clark's Early during 1935 and possibly in Globe during 1936, but it had no effect on Purple Pritchard, on Stokesdale, 0r on the varie- ties listed in Table 29. Supplements: During the 1932 season, the guard rows of each of the fourteen fertilizer plats at the Weslaco station were treated with sul- phates of manganese and iron, applied about the plants at the time of the final thinning. The plants in the first row of each plat received iron sulphate at the rate of fifty pounds per acre, while the fourth row in each plat received a similar application of manganese sulphate. Results of the test with these materials are presented in Table 33. Plants which receive the iron sulphate supplement produced slightly less puffy fruit than the untreated plants, and this also held true for the plants that received manganese sulphate. However, the differences were not found to be sig- nificant, as the chi square values for the two periods of the test were 0.889 and 0.172, respectively. Table 33. Effect of manganese and iron supplements 0n pufling 0f Break 0’Day—-\7Veslac0, spring 1932. May 27 - June 6 Treatment Rate per A. No. No. Per cent No. No. Per cent normal puffed puffed normal puffed puffed None . . . . . . . . . . . . . 30S 310 50 562 378 40 FeSOa, . . . . . . . . . 5O 225 250 52 608 442 42 MgSO-z . . . . . . . .. 50 313 310 50 567 373 40 Discussion: The lack of agreement between the results secured at College Station and at Weslaco can most readily be explained by dif- ferences in soil type and soil fertility between the two locations. The Lufkin fine sandy loam on the Main Station horticulture farm has a shallow surface layer and is lacking in natural fertility. Crops respond well to applications of commercial fertilizer on this soil. In contrast, the deep alluvial soil types of Substation N0. 15 are somewhat heavier and vastly more fertile. The application of commercial fertilizers under these conditions would not be expected to have the same efiect as at College Station. In the work of Sando (14) previously referred to, seven different fer- tilizer ratios were applied to plats of the Globe variety. The nitrogen varied from 1 to 7 per cent, the phosphoric acid from 5 to 10 per cent, and the potash from 0 to 8 per cent. All plats contained some pufi. The author says that “complete counts could not be made, owing to the de- struction of vines by a flood before the end of the season, but enough observations were made to show that within the limits used varying quantities of fertilizer elements did not influence the production of hol- 4O BULLETIN NO. 541, TEXAS AGRICULTURAL. EXPERIMENT STATION 10w fruit.” No data are presented. It seems possible that had sufiicient data been collected, a significant difference might have been found be- tween fertilized and unfertilized plants. The Work of Grist (3) shows that the application of fertilizers to soil deficient in this respect has a decided influence on the water content of tomato plants. Applications of nitrogen, phosphorus, and potassium car- riers increased the proportion of water in the tops slightly and increased the per cent of bound water much more. They also reduced the rate of drying of the tops after being cut off. If the expression of puffing were greatly influenced by the amount of free water within the plant during a relatively brief period in its early development, it is conceivable that the observed decrease of puff with the use of fertilizer at College Station was influenced by an increase in the proportion of bound water in these plants. It is also possible that this may have a bearing on the varietal and strain differences observed. However, the author just cited considers that “the concept of bound water as an explanation of increased water content, decreased rates of transpiration and dehydration, increased hardiness, etc., in plants appears to be more or less unsatisfactory.” Fertilizers might influence the amount of pufiing by their effect on such things as cell permeability and structure of tissues. That fertilizers have been shown to influence a factor directly affecting amount of puffing would seem to be a step in reaching an explanation of a character Which is highly com- plicated in its expression. Disease Southern Blight: An important result of continuous cropping on the same land year after year is the accumulation of disease organisms. Since one aspect of the work at College Station is the development of desirable strains, plants have been grown on the same piece of ground three years in succession in order that disease-resistant types might be selected. Only one disease—southern blight, caused by Sicllerotium r0lfsii—was at all prevalent. The possibility that the amount of puffing might be changed because of the activity of. this parasite was investigated by comparing Table 34. Comparison of fruit fl'01ll normal and diseased plants, College Sta- tion, 1935. Based on total fruit at first harvest. No. fruits _ Condition No. Value of* Variety of plants chi square plants Normal Puffed Dwarf Champion 3S0 . . . . . . . . . . . . . Normal 15 119 46 Diseased 10 76 17 2 .97 Kanora 366 . . . . . . . . . . . . . . . . . . . . . . Normal 15 228 29 _ Diseased 10 85 14 2.55 Marglobe 434 . . . . . . . . . . . . . . . . . . .. Normal 14 s2 s1 i Diseased 9 42 43 1 .95 Matchum 266 . . . . . . . . . . . . . . . . . . .. Normal 4 43 8 Diseased 8 68 22 1 .49 *Values of 5 or more are considered significant. FACTORS AFFECTING THE AMOUNT OF PUFFING IN TOMATOES 41 results for diseased and normal plants of four varieties (Table 34). In no case was the difference significant. In cases where the plant was seen to be dying, all fruits which were large enough were examined. The pro- portion of fruit set before and after the plant became diseased are not known. It is possible that a comparison of these groups would show a significant difference. Friend (7) found a larger amount of puffing “Where a larger number of the plants showed marked evidence of decline toward the end of the season.” Blossom End Rot: During the course of the greenhouse experiments in the spring of 1935 considerable blossom end rot was observed after June 6. Nearly 34 per cent of the fruits secured from the low water table lot after this date were afiected, while only 7 per cent of the fruits from the high water table lot had the disease during the same period. When per cent of puff for all fruits is considered, a higher proportion of fruit from the low water table has puff than does that of the other group. The proportion of puffed fruits among those affected with blossom end rot is about the same as for all fruits in each water treatment (92 and 94 per cent in one case and 85 and 92 per cent in the other). Since this is true and the proportion of puffed fruits in both lots is high, there does not appear to be a close relationship between the two. Pollination Most of the work done elsewhere on pollination has been on greenhouse tomatoes. This has been reviewed by Schneck (15) in his report on methods of pollination. A point of interest in this and other publications has been the abnormal development of the fruit resulting from inadequate pollination. On page 38 of his report Figure 20 illustrates abnormal de- velopment of a Bonny Best fruit which had been unpollinated. One seed locule is fairly well developed. The others have been nearly filled by the over-grown cross walls which make a fairly solid fruit. This would be _ classed as a puffed fruit in our work, but it is not typical. Bailey (2) illustrates a similar condition, although not so pronounced. An uncut fruit poorly developed on one side is also illustrated. Such a condition is unusual among puffed fruits. Munson’s illustrations (11) are similar to Bailey’s. Fletcher and Gregg (5) used different amounts of pollen——an excess, a small amount, and only a few grains. Fruits resulting from the use of a large amount of pollen were normal. Fruits developing after pollination with a small amount of pollen were much smaller and gave evidence of what would be classified as a moderate degree of puff, judging from the illustration. Fruits resulting from the application of only a few pollen grains also were small and contained very few seeds. While it is diflicult to judge from the figure, these last fruits obviously do not ex- hibit typical puffing, although there is indeed a marked similarity to this condition. White (23) contrasts photographs of an unpollinated cluster of Carter Sunrise with one resulting from hand pollination. Fruits of the former are angular and have the external appearance of those puffed. All of the flowers on 25 plants of Marglobe 434 grown in the field at College Station were hand pollinated during the first period of the 1935 42 BULLETIN NO. 541, TEXAS AGRICULTURAL EXPERIMENT STATION season. Pollination was effected by picking off the stamens of open flowers and transferring the pollen to the stigma by means of a pair of forceps. -The puifing record is compared with that of 25 similar plants from the same lot in Table 35. During this first period the fruits resulting from hand pollination had significantly less puff than those unpollinated. During the second period when neither was pollinated the check had slightly less puff but the difference was not significant. Table 35. Effect of hand pollination on puliing in the field (Marglobe), Col- lege Station, 1935. Based on total harvestable fruit for each period. First period Second period Treatment No. No. Per cent No. No. Per cent normal puffed puffed normal puffed puffed Hand pollinated first period only. . . 96 173 64 295 102 27 Hand pollinated neither period... . . 62 1so 14 267 s6 24 Chi square . . . . . . . . . . . . . . . . . . . . . . . . . 6.08 . . . . . . . . . . . . . . . . . . 0.176 This evidence on the influence of pollination on puffing of the fruit is supported by other observations. The cumulative evidence from both greenhouse and field of a critical period about the time the fruit is setting favors an effect from pollination and, presumably, opportunity for fertili- zation. The observed effect of high temperature on the proportion of fruits puffed may be through its influence on pollen tube growth. Smith and Cochran (16) found that the percentage of tomato pollen grains germi- nating at 100°F. ranges from 0.1 to 6.3. Eighty-four hours after pollina- tion no tube had grown more than 2 mm. in length at this temperature. Since maximum greenhouse temperatures sometimes exceeded 110°F., it seems likely that damage to the pollen by heat may have been the domi- nant factor in the 100 per cent pufling observed during this period. It hardly seems possible that the effect of the various hereditary and environmental factors is limited to their influence upon pollen tube growth and subsequent fertilization of the egg. There are several reasons for thinking this. Attention has been called to the appearance of fruits known to be “puffed” from lack of adequate pollination. This is not typical of ordinary puffing. While fruits that are puffed the worst usually have no normal seeds, many fruits puffed rather badly appear to have a full complement of seeds. On the other hand, fruits with little or no puff have been observed Without a sign of seed development. The final con- clusion will depend to some extent on the exact definition of puffing used. Po-sition of Fruit At the time the puffing data obtained in the greenhouse during the spring of 1935 were recorded, the cluster from which the fruit was obtained was noted. These data can be found in Table 36 with compari- sons in Table 37. There is a marked and consistent rise in percentage FACTORS AFFECTING THE AMOUNT OF PUFFING IN TOMATOES 43 of puff from the first to the last clusters for plants in pots and for those with a 10w water table. This difference is not significant for the first three clusters, probably because of small amount of data. For the high water table lot the only significant difference is between the first and fifth clusters. Table 36. Position of fruit on the plant—spring 1935. Based 0n total fruits per cluster. Av. Treatment Cluster No. No. Per cent height normal puffed puffed (in.) 10-inch pots . . . . . . . . . . . . . . . . 1 23 22 49 23 ' 2 12 17 59 30 3 7 16 70 38 4 1 14 93 45 Low water table . . . . . . . . . . . . 1 14 42 75 20 2 12 49 8O 30 3 9 54 86 40 4 1 44 98 49 5 O 20 100 67 High water table . . . . . . . . . . . 1 23 75 77 21 2 22 82 79 3O 3 17 68 78 39 4 15 54 78 46 5 1 30 97 54 In comparing the same clusters of different lots no difference is found between the first clusters of the low and high water table lots, but there is a significant difference between the fourth clusters of these two lots. This is to be expected since the first and fourth clusters of the high water table are about the same while these clusters of the low water table are different. The fifth clusters of both lots differ very little. The significant increase has thus occurred between the third and fourth clusters of the low water table lot and between the fourth and. fifth clusters of the lot Table 37. Comparison of different clusters within and between lots. Groups compared Values of * chi square Treatment Cluster Treatment Cluster 10-inch pots . . . . . . . . . . . . . . . 1 10-inch pots . . . . . . . . . . . . . 2 0.67 10-inch pots . . . . . . . . . . . . . . . 1 10-inch pots . . . . . . . . . . . . . 3 2.63 10-inch pots . . . . . . . . . . . . . . . 1 10-inch pots . . . . . . . . . . . . . 4 9.25 Low water table . . . . . . . . . . . . 1 Low water table . . . . . . . . . . 2 0.47 Low water table. . . . . . . . . . 1 Low water table . . . . . . . . . . 3 2.18 Low water table . . . . . . . . . . . . 1 Low water table . . . . . . . . . . 4 10.2 Low water table . . . . . . . . . . . 1 Low water table . . . . . . . . . . 5 6.12 High water table . . . . . . . . . . . 1 High water table . . . . . . . . . 2 0.15 High water table. . . . . . 1 High water table . . . . . . . . . 3 0.32 High water table . . . . . . . . . . . 1 High water table . . . . . . . . . 4 0.068 High water table . . . . . . . . . . . 1 High water table . . . . . . . . . 5 6.37 Low water table . . . . . . . . . . . . 1 High water table . . . . . . . . . 1 0.045 Low water table . . . . . . . . . . 4 High water table . . . . . . . . . 4 8.59 Low water table . . . . . . . . . . . 4 10-inch pots . . . . . . . . . . . . . 4 0.68 Low water table . . . . . . . . . . . 5 High water table . . . . . . . . . 5 0. 65 ‘Values of 5 or more are considered significant. 44 BULLETIN NO. 541, TEXAS AGRICULTURAL EXPERIMENT STATION with the high water table. The fourth cluster of the 10w water table and the fifth cluster of the high water table were setting at about the same time and therefore under similar environmental conditions (see discus- sion under temperature). A difliculty in comparing fruit from clusters on the same and different plants lies in the fact that the periods of fruit setting may overlap yet do not ordinarily coincide. This means that, among clusters, the fruits usually set and develop under somewhat different environmental condi- tions and for this reason differences in amount of puff cannot be assigned to position on the plant. While this may be an important environmental factor, it can not, under these conditions, be distinguished from other factors. Hereditary Factors With such ready response to‘ environmental conditions, it is essential to make comparisons only when the lots being compared are grown under very similar conditions. Further, pufling results should be compared only where the fruits have developed over approximately the same period. This has been discussed in connection with replicated plantings of Mar- globe 434 grown at College Station during the 1935 season. When a comparison is made within these limits identical lots have been found to vary no more during the first part of the fruiting season than would be expected on a basis of chance sampling. Where a significant difference is found between lots for the same period, grown under comparable condi- tions, the possibility that such difference may have a genetic basis pre- sents itself. It does not necessarily follow that a difference obtained under such conditions is always genetic, as is amply illustrated by the variation between lots of Marglobe 434 during the second period (Table 16), but there is excellent reason to believe that important genetic differences exist among many varieties and sometimes among strains of the same variety. The evidence for this has to do with the range in amount of pufiing of varieties, strains, and replications, with the consistency of varietal differences, with a comparison of individual plant selections within a variety, and finally with the results of intervarietal crosses. Varieties and strains: Varietal differences have been discussed in pre- vious publications (6, 25). This work is presented here in somewhat greater detail and later results are added. Some attention .has been called to varieties in the discussion of change in amount of puffing with advance in the season (Tables 12 to 19). In general the Globe and the very large fruited types, such as Beefsteak, have considerably more puff than varieties of the Bonny Best type. The small-fruited tomatoes, with the exception of Pomodora, have very little puff. Because of the com- mercial importance of the variety, the uniformly large amount of pufiing found in Marglobe is of interest. Globe, one of its parents, also has a consistently high amount of puff. Within the limits of sampling error the percentage of puff should be the result of the interaction of genetic and environmental factors, external and internal, the latter environmental factors conditioned in part by FACTORS AFFECTING THE AMOUNT OF PUFFING IN TOMATOES 45 the former. Under comparable environmental conditions greater dif- ferences would be expected, on the whole, between varieties than between strains, and likewise greater differences between strains and selections than between replicated plantings having in the aggregate the same heredity. During the 1932 season at College Station the range in variation for 55 varieties and strains for the June picking was from 18 Table 38. Range in percentage 0f pufiing 0f different lots of the same variety, College Station 1932. une ul No. J J y lots Variety i Lowest Highest i Range Lowest Highest Range | . 4 Bonny Best . . . . . . . . . . . . . . 29 S2 23 15 42 27 4 Break O'Day . . . . . . . . . . . . . 49 52 3 26 34 8 4 Earliana . . . . . . . . . . . . . . . . . 18 57 39 10 27 17 4 Globe . . . . . . . . . . . . . . . . . . . 36 77 41 32 57 25 4 Gulf State Market . . . . . . . . 24 52 28 13 34 21 11 Marglobe . . . . . . . . . . . . . . . . 55 83 28 57 79 22 55 All Varieties . . . . . . . . . . . . . . 18 \ 83 65 8 79 71 \ (Earliana 12) to 83 per cent (Marglobe 41), and for July from 8.4 (Acme 67) to 79 per cent (Marglobe 11). The range for different lots of six variations is given in Table 38. The range for all varieties during June 1932 is 65 points. The greatest range for any variety at this harvest is 41 points for Globe. For Jul-y the range for all varieties is somewhat greater——71 points; the greatest range for any single variety is 27 for Bonny Best. If the 11 lots of Marglobe Were a representative sample of the 55 lots including all varieties tested that year, and the amount of puffing were due entirelry to environmental fac- tors without respect to genetic differences, the range of variation of these 11 lots would be expected to approach that of the entire group. This is obviously not the case. No lot of Marglobe has less than 55 per cent puff at the June harvest, a figure much higher than the 18 per cent of Earliana and approximating the upper limit for that variety. For the July harvest there is an even greater discrepancy between the lowest lot of Marglobe (57%) and the lowest lot of all (Acme, 8.4%). Considering the highest strain of each of the three varieties (Bonny Best, Break O’Day, and Gulf State Market, involving a total of 12 lots) not one comes within 30 points of the lot with the greatest amount of puff (a strain of Marglobe) for either June or July (Table 38). Results for the two harvest periods are fairly consistent. Without exception, the lot with the lowest amount of puff at the June picking was also the lowest for the variety at the second harvest. The highest lot was the same for the two periods in four of the six varieties; one of the ex- ceptions was Marglobe. This consistency might, with reason, be assigned to either environmental or genetic factors primarily. However, the genetic complement can not have changed materially, while certain phases of the environment are known to have changed. 46 BULLETIN NO. S41, TEXAS AGRICULTURAL EXPERIMENT STATION Another point of evidence in favor of the importance of genetic factors is the difference in variation among the different lots of the varieties listed. Marglobe with 11 lots had a much smaller range at the first picking than Earliana and Globe with only 4 lots each, and about the same as Gulf State Market. At the second picking its range was less than that of either Bonny Best or Globe. The four lots of Break O’Day have a very small total range at each picking. In an earlier paper (25) it was concluded that the four lots of Break O’Day represent no more than two slightly different strains, while the four lots of Globe represent three distinct strains. This leads to the conclusion that the thing that prevents the lots of one variety from varying more than might be expected 0n a basis of chance is genetic similarity, and where lots of one variety do vary widely under similar environmental conditions much wider genetic differences with respect to puffing exist. Consistency of behavior of replicated plantings over the same period has already been noted. In a consideration of results secured over a period of ryears, marked changes in environmental factors must be taken into consideration. Bonny Best, Dwarf Champion, Early Detroit, and Gulf State Market as grown at College Station will be discussed from this standpoint. Plant- ings of the same lot made during different seasons will be considered first. Inasmuch as the same variety did not occupy precisely the same position each year, soil variation may have been a factor contributing to the degree of variability, Bonny Best 33 and 39 were grown both in 1932 and in 1933 (Tables 13 and 14). Both lots had less puff the second year. No. 33 had considerably more puff than No. 39 the first season, but slightly less the second. The hereditary factors remained the same, yet the difference between the two seasons seemed to have greater effect on No. 33 than on N0. 39. Since No. 33 had more puff in 1932, the same relationship might be expected with a change in environmental condi- tions. Two or three explanations appear promising. If, say, five per cent were the irreducible minimum for the variety, one would expect little or no difference between the two strains when conditions were highly favor- able for normal fruit development, but a rather wide difference might be possible when conditions favored a large amount of pufi. As a second consideration it seems likely that the change in environmental conditions was not precisely the same for both lots. A third point is the probability that each genetic type responds perhaps in a different way or at least at a different rate from another genotype with any specific change in the environment. For example strain A might have 30 per cent puff under one set of moisture conditions and 60 per cent under another, while strain B might have 30 per cent puff under the first and only 45 per cent under the second. Incidentally it is not known that the fruits of these strains of Bonny Best set in the same proportions over exactly the same period. Gulf State Market 10 and 32 were grown both in 1932 and in 1933. In this instance No. 1O had less puff than No. 32 in 1932 but a similar low amount for the first picking of 1933. The situation thus far is similar FACTORS AFFECTING THE AMOUNT OF PUFFING IN TOMATOES 47 Table 39. Comparison of varieties—-Weslac0, spring 1926. Based 0n 25 fruits per picking. Per cent puffed Variety Row No. June 4 June 15 A and M First Early . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 0 0 Acme . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 0 8 Acme . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54 0 2 Avon Early . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 0 O Avon Early . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 0 0 Beauty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 0 20 Brimmer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 0 0 Burbank Early . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 0 a 0 Burbank Early . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48 0 0 Cooper's Special . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 60 48 Cooper's Special . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46 80 60 Coreless . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 80 80 Coreless . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 70 16 Earliana . . . . . . . . . . . . . . ; . . . . . . . . . . . . . . . . . . . . . . . 21 0 0 Early Detroit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 3O 20 Early Detroit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47 O 12 Early Michigan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 0 0 F ordhook First Early . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 0 0 Globel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51 80 40 Globel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . S6 60 72 Globe? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53 80 40 Globe3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 80 68 Globe3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 80 52 Globe3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 80 72 Gl0be3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3O 84 68 Globe3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 80 72 Globe3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 80 76 Globe?» . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58 60 48 Globe3 . . . . . . . . . . . . . . . . . . . . . _ . . . . . . . . . . . . . . . . . 59 6O 72 Gulf State Market? . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 2O 60 Gulf State Market3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 60 28 Gulf State Market3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 4O 32 Hummer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 O 64 June Pink . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 0 4 June Pink . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 20 4 June Pink . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 0 0 June Pink . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 40 28 John Baer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 0 0 John Baer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 0 8 John Baer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57 20 8 Manyfold . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 O 8 Matchless . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 0 12 Norduke . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 60 44 Norton . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 O 36 Paragon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 60 28 Perfect First Early . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 0 4 Perfect First Early . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 0 20 Perfection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 2O 0 Rosy Morn .' . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 80 80 Rosy Morn . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 70 16 Red Field Beauty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 4O 8 Red Field Beauty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 0 8 Red Head . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 6O 16 Red Head . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 40 36 Self Pruning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 90 20 Truckefs Favorite . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2S 0 44 1From Burpee. 2Fr0m Ferry. sFrom Livingston. 48 BULLETIN NO. 541, TEXAS AGRICULTURAL EXPERIMENT STATION Table 40. Comparison of varieties—\Veslaco, spring 1927. Based on total fruits for first two pickings; 25 fruit sample at third picking. June 7 June 14 June 22 Per cent puffed Variety* R 0 W No. fruit N0. fruit N0. fruit No. Normal Puffed Norma] Puffed Normal Puffed 7 14 22 Acme . . . . . . . . . . . 34 5 0 31 0 25 0 . . . . . . . . . . . . . . . . . . . . . Beauty . . . . . . . . . 28 11 3 34 1 23 2 . . . . . . . . . . . . . . 8 Beauty . . . . . . . . . 29 4 O 14 O 25 O . . . . . . . . . . . . . . . . . . . . . Beauty . . . . . . . . . 31 1 O 12 O 22 3 . . . . . . . . . . . . .. 12 Beauty . . . . . . . . . 32 5 1 41 0 24 1 . . . . . . . . . . . . . . 4 Beauty . . . . . . . . . 23 3 0 47 0 23 2 . . . . . . . . . . . . . . 8 Burbank Early.. 48 168 11 191 15 24 1 6 1 7.3 4 Cooper's Special. 17 13 4 23 7 22 3 24 23 12 Coopefs Special. 18 35 16 122 21 23 2 31 15 8 Cooper’s Special. 19 46 17 170 55 22 3 27 24 12 Cooper's Special. 21 57 15 148 30 23 2 21 17 8 Coopers Special. 22 27 12 58 12 21 4 31 17 16 Duke of York. . . 49 6 0 24 0 24 1 . . . . . . . . . . . . . . 4 Duke of York... 51 . . . . . . . . . . . . .. 3 0 0 4 . . . . . . . . . . . . . . . . . . . .. Dwarf Cham- pion Early. . .. 57 50 1 55 1 25 O 1.9 1 8 . . . . . .. Dwarf Giant. . . . 58 . . . . . . . . . . . . . . 3 0 0 2 . . . . . . . . . . . . . . . . . . . . . Early Detroit. . .. 35 5 0 5 3 25 O . . . . . . . . . . . . . . . . . . . . . Early Detroit. . .. 36 11 O 17 5 22 3 . . . . . . . 23 12 Fordhook Flint. . 45 27 O 123 _ O 23 2 . . . . . . . . . . . . . . 8 Globe . . . . . . . . . . 1 7 5 14 10 4 21 . . . . . . . 42 84 Globe . . . . . . . . .. 2 ,4 2 17 1O 13 12 . . . . . .. 37 48 Globe . . . . . . . . .. l0 3 3 24 11 18 7 . . . . . .. 31 28 Globe . . . . . . . . . . . 2O 8 2 28 9 21 4 . . . . . . . 24 16 Globe . . . . . . . . . . 3O 14 1O 47 16 2O 5 42 25 2O Globe . . . . . . . . . . 4O 2 O 14 5 17 8 . . . . . . . 26 32 Globe . . . . . . . . . . 5O . . . . . . . . . . . . . . 1O 2 18 7 . . . . . . . . . . . . .. 28 Globe . . . . . . . . . . 59 2 2 1 1 21 4 . . . . . . . . . . . . . . 8 Globe . . . . . . . . . . 6O 2 O 6 3 12 13 . . . . . . . . . . . . . . 52 Globe . . . . . . . . . . 12 5 2 O O 2O S . . . . . . . . . . . . . . 2O Globe . . . . . . . . . . 13 7 4 0 1 7 3 . . . . . . . . . . . . . . . . . . . . . Globe . . . . . . . . . . 14 4 O O 9 19 6 . . . . . . . . . . . . . . 24 Globe . . . . . . . . . . 15 2 1 O 4 18 7 . . . . . . . . . . . . . . 28 Globe . . . . . . . . . . 16 4 1 O 6 12 13 . . . . . . . . . . . . . . 62 Gulf State Mkt.. 2s ss a 6s 11 22 s ‘l’ 9.4 1s 12 Gulf State Mkt. . 26 6O 12 51 1O 25 O 17 16 . . . . . . . Gulf State Mkt. . 27 5O 1O 67 8 22 3 17 11 12 June Pink . . . . . .. 3 151 2 100 8 24 1 1.3 7.4 4 4 June Pink . . . . . .. 4 128 2 53 4 23 2 1.5 7.0 8 1 June Pink . . . . . .. 5 94 8 67 1 11 6 7.8 1.5 . . . . . .. June Pink . . . . . . . 6 99 6 85 6 24 1 5.7 6.6 4 June Pink . . . . . .. 7 187 13 84 11 21 4 6.5 12 16 Kanora . . . . . . . . . 47 5 2 23 10 17 8 . . . . . . . 30 32 Long Keeper. . . . 42 7 2 88 O 24 1 . . . . . . . . . . . . . . 4 Louisiana Pink. . 8 30 17 103 44 20 5 36 30 20 Louisiana Pink. . 9 42 25 3O 11 18 17 37 27 68 Louisiana Pink . . 11 32 13 28 16 16 9 29 36 36 Louisiana Red . . 55 44 23 132 51 18 7 34 28 28 Magnus . . . . . . . . . 37 2 1 4 2 21 4 . . . . . . . . . . . . . . 16 Marglobe . . . . . . . 52 21 6 21 12 1O 15 22 36 6O Marglobe . . . . . . . 53 1O 4 26 15 12 13 29 i 37 52 Marvelosa . . . . . . 43 18 3 58 1 25 O 14 1. 7 . . . . . . . *Each row of the same variety represents a different seed source except Globe rows 1, 2, 10, 20, 30, 40, 50, 59 and 60. FACTORS AFFECTING THE AMOUNT OF PUFFING IN TOMATOES 49 Table 40. Comparison 0f varieties—Weslaco, spring 1927. Based on ‘total fruits for first two pickings; 25 fruit sample at third picking.—Continued June 7 June 14 June 22 _ Per cent puffed Var1ety* RNo w No. fruit N0. fruit No. fruit o. Normal Puffed Normal Puffed Normal Puffed 7 14 22 Mikado . . . . . . . . . 46 7 2 15 1 21 4 . . . . . . . 6. 3 16 Perfect First Early . . . . . .. 56 84 11 114 2O 24 1 12 15 4 Rosy Morn . . . . . . 44 16 6 28 2 18 7 27 6.7 28 Self Pruner . . . . . . 23 62 13 1S0 39 25 O 17 21 . . . . . . . Sell Topper. . . .. 24 33 6 107 27 2S O 15 2O . . . . . . . Truckers} { 39 1 2 5 1 18 7 . . . . . . . . . . . . . . 28 Favorite ‘ ' ‘ ‘ 41 . . . . . . . . . . . . . . 5 1 20 5 . . . . . . . . . . . . . . 20 *Each row of the same variety represents a different seed source except Globe rows 1, 2, 10, 20, 30, 40, 50, 59 and 60. to that of Bonny Best. At the second picking No. 10 had about 1O points more puff than No. 32. The third point mentioned above may be the explanation for this behavior. Results of tests of varieties secured at College Station and at the Lower Rio Grande Valley Station (Tables 39 to 46) have been fairly consistent. Close correspondence could not be expected because of difference in growing conditions which may easily be greater during the same season than between two seasons at either location, because the strains under test were not always identical, and because the error due t0 small sam- ples was sometimes rather large at one or both points. The high per- centage of puff in Marglobe has been evident at both places. A few varieties such as Acme and John Baer, June Pink, and certain strains of Earliana and Gulf State Market have given comparatively low percentages at both places. While this bulletin is concerned chiefly with the role of variety as a factor in determining the amount of pufling, all available puff- ing data on varieties have been given and so can be considered in an esti- mate of the commercial desirability of any variety. All data appear in tables except the varietal results at Weslaco during the 1931 spring season. These give Break O’Day 368 normal fruits to 84 puffed (19%), and Cooper’s Special 324 normal to 145 puffed (31%). Numbers of puffed and normal fruit have been presented when not already published, as well as percentages of puff, to give some idea of the validity of the latter. While such field data are unsatisfactory for a close comparison between two varieties, they do give an indication of the relative amount of pufling. Calculation of varietal results to a standard set of environmental condi- tions would be an ideal method of comparison, but this is as yet im- possible. During the six-year period under consideration (1931 to 1936) the range in percentage of pufiing for Bonny Best at College Station has been from 5.5 (determined from only 36 fruits) to 52. This includes a total so BULLETIN NO. s41, TEXAS AGRICULTURAL EXPERIMENT STATION 8.8 8.8 2 3 2 88 2 2.8 2 82 2.8 2.22 88 2 . . . . . . . . . . . . . .822 883 22 8.2 2 2 2 2 88 8.8 88.28 88.2 3.8 2 2 . . . . . 88E 883 8. 8.8 2 2 2 2 3. 2 2 2.82 88.2 2.2 88 2 . . . . . . . . . 188E 8S; 22 2.2 82 88 2 2 28 2.2 2.88 88.8 88.3 2 2 . . . . . . ..........8Em 883 2 82 2 88.8 3.2 2 82 2 28 3.8 8.82 88 2 1.888282 88888 :80 28 2 82 2.8 2.2 2.8 2 3 82 2.8 2 2 1.8888822 888w :80 3 2 82 2.8 2.8 2 82 3.88 88.8 3.2 28 82 . c8832 888w :80 82 2 82 2.2 3.82 88 S 3.88 88.8 3.82 2.. 82 2.888282 882w :80 3 2 88 2.8 3.2 88 2 8.88 2.8 2.2 3 .2 . . . . . . . . . . . . 8820 22 3 . . . . .. 2.8 3.8. 3 88 88.82 2.2 2.8 2 82 . . . . . . . . . . . . . . . . 8820 88 2 2.8 88.82 2 2 2.2 2.2 88.8 88 22 . . . . . . . . . . . . . . . . . . 18820 82 3 . . . . .. 2.2 88.22 3 22 3.2 88.2 88.2 82 22 . . . . . . . . . . . . . . . . . . .8820 3 82 . . . . .. 3.8 88.22 3 82 2.28 2.2 2.2. 3 2 . . . . . . . . . . . . . 8820 2 88 . . . . .. 2.2 2.2 3 22 3.3 88.2 3.2 88 2 . . . . . . . . . . . . .8820 2 88 . . . . .. 3.8 2.22 3 2 88.88 2.2 2.8 28 2 . . . . . . . . . . . . . . . . . . 18820 88 28 3 2.8 88.22 2 2 2.28 88.8 8.8 88 2 . . . . . . . . . . .8820 88 88 88.8 2.2 2 82 2.2 3.8 2.8 28 2 . . . . . . . . . . . . . . .8820 2 2. . .. . 2.8 3.2 3 3 88.28 2.8 2.2 82 2 . . . . . . . . . . . 8820 88 2 3.2 2.3 3 8 2.82 3.8 88.2 22 2 . . . . . . . . 88880 88 88 . 2.2 3.2.2 88 88 2.3 88.8 2.2. 2 2 . . 88880 28 88 .. 2.2 2.22 88 I 2 2 2.2 88.8 2 2 . . . . . . . . . . . . . . 88880 82 22 .. 88.8 88.82 2 8 88.3 2.8 2.2 28 2 . . . . . ......:.8:8> 88 88:5 82 2.2 . . .. 2.8 2.2 22 88.22 88.8 88.2 22 2 ...........8:8>...8 88:5 3 3 . 3.8 2.3 88 28 88.82 8.2 88.2 22. .. ...........88888m 8.888880 3. 2 2 3.8 . .282 2 2 2.22 3.8 88.82 3 8 . . . . . . ....._8U88w 8.888880 82 2 2.8 88.3 88 8 8.2 2.8 3.8 8 8 ..........._88888w 8.888880 22 82 22 3.2 3.88 3 S 3.2.2 2.2. .22 3 2 ..........._8E88m 8.888880 22 2 3.8 88.8 88 2 88.88 2.2 2.2 8 2 .........._88888w 8.888880 2 2 82 2.2 . 3.2 88 8 88.2 3.2 88.2. 88 2 .....388m 8.88880 82 8.8 82 3.8 2.3 2 8 3.88 88.8 2.2 3 2 . . . . . . . . . ...;€8m 8.8220 8.8 8 8 8.8 2.2 3.88 88 8 3.882 3.2 2.2 3 . 2 . . . . ....8E88§m 2.8 2 2 2 88.8 2.88 8.2 2.3 3.8 2.3 2 2 . . . . . .......8E888=m 2 22 82 2.2 82.82 8.2 3.3 88.8 3.8 88 .. ...................>8=88m ©N .. ... .8 .-............-....~mw5..fl~wm wwmsm 1822202 038cm GCCQZ wwmsm 8.85.82 2 22 .22 . 82.8 .882 88E .882 8E8 .884 .82 .82 _ 30M 18.3w >88€m> 88888 268 28m N 38h 22 85;. m2 85%. nw-JMSQ £0880 nan 35.2w 130w m9 f-Mmo? i0 womui dumn wfimufim .eva_mub?llmomwomaa> a0 2632289500 .28 0112B 51 FACTORS AFFECTING THE AMOUNT OF PUFFING IN TOMATOES c2 2 2 24. 2.2 8.2 8.2. 2e 2.3 8. .. . . ...r..25£. :00 22. 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NN 92:2. N2 25:2. 220H:2w=oD|l.M-22v2o2a 22050 HOH 35.2w 2520a HO 222M295 GO Uvndmn -WNG.H M-Suim ..6vfl2mvb?lnv2wfl2nfl> m0 525726222299 ‘HQ 02-258 52 BULLETIN NO. 541, TEXAS AGRICULTURAL EXPERIMENT STATION Table 42. Comparison of varieties—Weslaco, fall 1929. Based on No. 1 fruits for two pickings. October 30 November 16 Per cent pufied Variety Row No. fruit No. fruit No. Normal Pufled Normal Puffed Oct. Nov. Cooper's Special . . . . . . . . . . . 2 1 40 7 54 98 89 Earliana . . . . . . . . . . . . . . . . . . 15 as 71 ss 43 6s 3s First Early . . . . . . . . . . . . . . . . 6 36 44 39 26 55 40 Globe . . . . . . . . . . . . . . . . . . . . 13 O 14 1 26 . . . . . . . . . 96 Gulf State Market . . . . . . . . . 11 5 51 14 63 91 82 John Baer . . . . . . . . . . . . . . . . 9 27 81 S4 85 75 61 Marglobe . . . . . . . . . . . . . . . . . 3 3 14 7 2 . . . . . . . . . 79 Marglobe . . . . . . . . . . . . . . . . . 7 3 29 7 42 91 86 Marglobe . . r . . . . . . . . . . . . . . 8 4 41 10 57 91 85 Marglobe . . . . . . . . . . . . . . . . . 10 3 22 3 29 88 91 Marglobe . . . . . . . . . . . . . . . . . 12 2 43 3 31 93 91 Marglobe . . . . . . . . . . . . . . . . . 14 0 22 5 22 . . . . . . . . . 82 Norton . . . . . . . . . . . . . . . . . . . 4 1 28 10 41 97 8O Table 43. Comparison of varieties-Weslaco, spring 1930. Based on approxi- mately 100 fruits. Row Date No. No. Per cent Variety " No. taken normal puffed puffed Avon Early . . . . . . . . . . . . . . . . . . . . . . . . 12 May 30 70 30 3O Bonny Best . . . . . . . . . . . . . . . . . . . . . . .. 4 May 27 55 45 45 Clark's Early . . . . . . . . . . . . . . . . . . . . . . . 24 June 2 56 44 44 Coopefs Special . . . . . . . . . . . . . . . . . . . . 2 May 27 11 89 89 Earliaha . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 May 30 57 43 43 Fargo . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 June 2 51 49 49 First Early . . . . . . . . . . . . . . . . . . . . . . . . 18 May 30 56 44 44 Globe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 May 30 42 69 62 Gulf State Market . . . . . . . . . . . . . . . . . . 14 " 30 47 63 57 John Baer . . . . . . . . . . . . . . . . . . . . . . . . . 10 May 30 56 44 44 Louisiana Pink . . . . . . . . . . . . . . . . . . . . . 8 May 27 54 46 46 Marglobe . . . . . . . . . . . . . . . . . . . . . . . . 1 May 27 23 77 77 Marglobe . . . . . . . . . . . . . . . . . . . . . . . . . . 3 " 27 1O 9O 90 Marglobe . . . . . . . . . . . . . . . . . . . . . . . . . . 9 " 30 15 85 85 Marglobe . . . . . . . . . . . . . . . . . . . . . . . . . . 11 " 30 11 89 89 Marglobe . . . . . . . . . . . . . . . . . . . . . . . . . . 13 " 30 5 95 95 Marglobe . . . . . . . . . . . . . . . . . . . . . . . . . . 15 " 3O 2 98 98 Marglobe . . . . . . . . . . . . . . . . . . . . . . . . . . 17 " 3O 4 96 96 Marglobe . . . . . . . . . . . . . . . . . . . . . . . . . . 19 ” 3O 9 91 91 Marglobe . . . . . . . . . . . . . . . . . . . . . . . . . . 21 " 30 19 102 84 Marglobe . . . . . . . . . . . . . . . . . . . . . . . . . . 23 June 2 7 93 93 Marglobe . . . . . . . . . . . . . . . . . . . . . . . . . . 25 " 2 10 90 90 Marglobe . . . . . . . . . . . . . . . . . . . . . . . . . . 27 " 2 21 79 79 Nicholson's 498 . . . . . . . . . . . . . . . . . . . . . 26 June 2 S9 41 41 Norton . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 May 27 40 60 60 FACTORS AFFECTING THE AMOUNT OF PUFFING IN TOMATOES 53 Table 44. Comparison of varieties—Weslaco, spring 1932. Based on total fruit harvested June 6. No. No. Per cent Variety normal puffed puffed Notes Bonny Best . . . . . . . . . . . . . . 15 15 50 Field grown Bonny Best . . . . . . . . . . . . . . . 66 34 34 Potted in cold frame Bonny Best . . . . . . . . . . . . . . . 42 28 40 Transplanted to field Break O'Day . . . . . . . . . . . . . 7O 3O 30 Earliana . . . . . . . . . . . . . . . . . 38 22 37 Fargo . . . . . . . . . . . . . . . . . . . . 74 26 26 Marglobe . . . . . . . . . . . . . . . . 6 23 79 Pritchard . . . . . . . . . . . . . . . . . 57 43 43 Whole Salad . . . . . . . . . . . . . . 52 14 21 Table 45. Comparison of varieties—Weslaco, pring 1934. Based on a 25-fruit sample at each of three pickings. Row No. No. Per cent Variety No. normal puffed puffed Bonny Best . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 63 12 16 Bonny Best . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 65 10 13 Bonny Best . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 59 16 21 Break O'Day . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 59 16 21 Chalk’s Jewel . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 64 11 15 Cooper's Special . . . . . . . . . . . . . . . . . . . . . . . . 8 51 24 32 Dwarf Champion . . . . . . . . . . . . . . . . . . . . . . . . 312* 52 11 18 Dwarf Champion . . . . . . . . . . . . . . . . . . . . . . . . 311* 24 16 4O Ferry’s 100 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 70 5 6.7 June Pink . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 73 2 2.7 Gulf State Market . . . . . . . . . . . . . . . . . . . . . . 7 S4 21 28 Gulf State Market . . . . . . . . . . . . '. . . . . . . . . . 313* 124 7 5.3 Gulf State Market . . . . . . . . . . . . . . . . . . . . . . 314* 32 4 11 Marglobe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 39 36 48 Morse Special 498 . . . . . . . . . . . . . . . . . . . . . . . 4 67 8 11 Pritchard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 49- 26 33 *Se1ection number. Table 46. Comparison of varieties-—\Veslaco, spring 1936. Per cent puif based 0n 100 fruits each harvest. May 20 May 28 June 10 Variety Row No. Mod. Severe Total Mod. Severe Total Mod. Severe Total Biltmore . . . . . . . . . . . . . . . . 22 20 21 41 28 14 42 34 20 54 Bonny Best . . . . . . . . . . . . . 18 13 7 20 13 7 2O 45 23 68 Break O'Day . . . . . . . . . . . . 6 59 13 72 46 10 56 62 21 83 Clark's Early . . . . . . . . . . . . 1 22 2 24 30 8 38 52 11 63 Glovel . . . . . . . . . . . . . . . . . . 4 36 5 41 72 9 81 70 1O 80 Glovel . . . . . . . . . . . . . . . . . . 12 63 11 74 54 7 61 73 4 77 Grothen Globe . . . . . . . . . . . 11 48 11 59 52 5 57 64 6 70 Gulf State Market . . . . . . . 8 38 19 57 30 11 41 49 16 65 June Pink . . . . . . . . . . . . . . . 10 34 14 48 22 11 33 . . . . . . . . . . . . . . . . . . L. S. U. No. 10 . . . . . . . . .. 16 47 4 51 40 14 54 69 16 85 Marglobe . . . . . . . . . . . . . . . 9 68 15 83 77 5 82 91 1 93 Marglobe . . . . . . . . . . . . . . . 14 59 10 69 61 8 69 73 19 92 Master Marglobe . . . . . . . . 19 54 14 68 59 6 65 58 24 82 Pritchard . . . . . . . . . . . . . . . 7 53 8 61 44 4 48 61 8 69 Pritchard . . . . . . . . . . . . . . . 13 52 11 63 42 6 48 84 2 86 Pritchard . . . . . . . . . . . . . . . 17 47 10 S7 47 8 55 51 28 79 Purple Pritchard . . . . . . . . . 15 12 12 24 28 7 35 51 13 64 Rutgers . . . . . . . . . . . . . . . . . 3 44 15 59 S7 3 60 74 13 87 Scarlet Dawn . . . . . . . . . . . . 2 46 8 54 54 16 70 88 3 91 Stokesdale . . . . . . . . . . . . . . 20 26 12 38 26 8 34 34 27 61 Texas Special . . . . . . . . . . . . 5 10 10 20 5 2 7 24 8 32 54 BULLETIN NO. 541, TEXAS AGRICULTURAL EXPERIMENT STATION of 24 lots, involving not over seven commercial strains, possibly fewer. Lots N0. 7 and No. 39 and their progeny were grown four years. Averages of the per cent of puffed fruit for each of four seasons are presented in Table 47. The summer and fall crops of 1934, although from the same Table 47. Average percentages of puflf for two strains of Bonny Best for different harvest seasons—College Station. Year No. 7 No 39 1932 26.1 22 2 1933 15.5 16 1 10341 46.0 48 1 19342 31.2 28 1 1935 23.4 26 S Average 28.6 28. 3 1 Summer 2 Fall plants, are listed separately, The widest difference, a. matter of 4.3 points, occurred during 1932. The average for the entire period is 28.6 per cent for No. 7 and 28.3 per cent for No. 39. In spite of wide varia- tion in environmental conditions during this four-year period it seems safe to assume that the two strains are either very similar 0r identical for those hereditary factors affecting pufling and that the variation be- tween seasons can definitely be assigned to environmental causes. In contrast to these results we find that averages for Gulf State Market 32 and 73 for about the same period show considerable difference between the two (Table 48). With the exception of the 1933 season No. 73 had very much less puff than did No. 32. It thus appears that strains, as well Table 48. Average percentages of puff for two strains of Gulf State Market for difierent harvest seasons—College Station. Year No. 32 No. 73 1932 43.2 1 1933 18.5 20 6 1934* 30.1 13 6 1935 16 8 Average 27. 1 14.9 *Fa1l crop. as varieties, that differ genetically can be distinguished over a period of years under field conditions. Such differences are apparent even though environmental conditions were only approximately the same for the strains and varieties being compared. Small differences might easily be masked by effects due to the environment where special precautions are not taken. Attention is called to certain low puffing strains listed in Table 19: Bonny Best 710, Earliana 440, Kanora 597, Marketeer 631, Stone 661, and Success 663. A globe strain received from France under the name “Globulariawilkomi” has a large, attractive fruit and gives indication of FACTORS AFFECTING THE AMOUNT OF PUFFING IN TOMATOES 55 a very 10w amount of puff under conditions at College Station. Such strains have immediate use in supplanting those with a higher proportion of puffed fruit in commercial production and are also useful in breeding to give varieties having a minimum of loss on this account. Selections: During the 1932 season at College Station seed was saved from individual plants exhibiting low and high amounts of puffing for 18 varietiesand strains. Seventeen of these paired selections were grown in adjacent rows the following season for comparison. Results for the 1933 season have already been presented in some detail (25). In spite of the fact that selections were in some cases based on a. small sample, the total fruit from the 17 selections for minimum pufling included 6684 normal and 1711 puffed fruits (20.4%) while the high puff selections produced 7525 normal and 2648 puffed fruits (26.0%). This difference was found to be significant. Since the plants were grown in adjacent rows in the field, the environmental influence must have been quite similar for each member of the pair as all plants were handled alike. Even sup- posing there were marked environmental differences between the paired selections, it hardly seems possible that most of the time these differences could have been favorable to less puff in the case of the low pufi selec- tions and to high puff for the high puff selections. The tendency of the uncontrolled environmental factors would’ be to mask rather than to emphasize small genetic differences. The inclusion of the selections for extremes of pufiing with the other lots, which were planted on land infested with the southern wilt organism for the purpose of selection for disease resistance, together with the ex- treme drought of the 1934 season, greatly reduced the number of paired selections by the elimination of one or even both members of a pair. While lot No. 116 of Dwarf Champion was lost in this way, No. 117, an additional selection, remained for comparison with No. 115. The inter- esting feature of the data is the contrast in behavior during the two har- vest periods (Table 49). No. 117 behaves more like the parent, which in Table 49. Comparison of selections of Dwarf Champion—College Station. N0. 115 No. 117 Per cent puff Per cent puff Year I » First? Second? Average First? Second? Average 19321 40 23 31.6 40' 23 31.6 1933 2O 19 _ 19.9 22 11 16.3 1934 . . . . . . . . . . . . . . . . . . . . . . . . ' 3O 28 29 . 2 1935 18 22 20. 2 49 6.6 27.7 1N0. 70, the parent from which the selections were made. zHarvest period. 1932 had a marked drop in amount of puff as the season advanced. The drop for No. 117 was not great in 1934 because of temperature complica- tions; the second period in this case was in the fall, which was fairly moist. No. 115 showed no appreciable decrease during 1933 and an actual increase during 1935. While this difference can not be considered fully established, it is an indication that such relative differences in S6 BULLETIN NO. 541, TEXAS AGRICULTURAL EXPERIMENT STATION amount of puff between strains or varieties found under one set of environ- mental conditions can not be expected to hold for another set of condi- tions, as may obtain earlier or later in the season, or in another year or geographical area. Later results with selections No. 139 and No. 140 of Gulf State Mar- ket 73 are as yet inconclusive. During 1933 there was a marked dif- ference between the two selections (Table 50). Practically no data were obtained during 1934. The following season the two selections were fairly close together. Additional data are necessary to establish a dif- ference between the two selections over a period of years. Table 50. Comparison of selections of Gulf State Market during different years—College Station. No. 139 No. 140 Year First Second Average First Second Average 1932* 24 13 18.5 24 13 18.5 1933 6.8 17 11.9 17 41 29 1935 . . . . . . . . . . . . . . .. 13 . . . . . . . . . . . . . . .. 1935 11 O . . . . . . . . 11 3.4 7 . 2 *No. 73 from which the selections were made. The two selections of Early Detroit did not show a difference in 1933. During 1935 one of these was compared with a similar selection from the original lot (No. 5). One had 22 per cent puff during the first period and 9.7 per cent during the second, with an average 0f 15.8. The correspond- ing figures for the other selection are 20, 7.9, and 13.9 for the average. Here again additional data are necessary for a satisfactory conclusion as to results to be expected for more than one season. Table 51. Results of crossing Dwarf Champion and standard types—College Station. Based on total fruit each period. First harvest period Second harvest period Per cent pufied Gen- _ Lot Year era- Loca- No. fflllll No. fruit No. tion tion Data Data __._______ taken taken First Second Norm. Puffed Norm. Puffed 176 1933 F1 14 June . . . . . . . 492 51 July . . . . . . . 324 35 9.4 14 289 1934 F2 2G July 25. . . .. 2 0 Oct.-Nov... 50 7 12 414 1935 F3 4A June 11.... 177 55 July 12..... 113 5 24 4.2 414 1935 Fa SA June 29.... 236 18 July 12..... 17 4 7.1 414 1935 F3 6A June 29. 322 25 July 12..... 48 8 7.2 14 414 1935 F3 7A June 13 . . . . 144 53 July 12. . . . . 193 9 27 4.5 415 1935 Fa 12B June 22.... 3S3 .94 July 15. . . . . 212 33 21 14 415 1935 F3 7C June 28 . . . . 283 33 July 16. . . . . 82 3 1O 3 .5 415 1935 F3 12C June 28. . .. 290 38 July 16..... 82 2‘ 12 2.4 415 1935 F3 3D July2 . . . . .. 251 17 July 16..... 26 0 6.3 415 1935 F3 7E July 4 . . . . .. 282 32 July 17..... 48 3 10 5.9 675; 1936 F4 . . . . . . . . . . . . . . 34 6 . . . . . . . . . . 43 24 15 36 681. 1936 F4 . . . . . . . . .. 77 6 . . . . . . . . .. 33 6 7.2 15 682‘ 1936 F4 . . . . . . . . .. 33 4 . . . . . . . . .. 20 6 11 FACTORS AFFECTING THE AMOUNT OF PUFFING IN TOMATOES 57 Table 52. Comparison of amount of pufl? in dwarf and standard segregates. Third generation. College Station, 1935. First Period Second Period Dwarf Standard Dwarf Standard Location Per Per Per Per No. N0. cent No. No. cent No. No. cent No. No. cent norm. puffed puffed norm. puffed puffed norm. puffed puffed norm. puffed puffed 4A . . . . . .. 18 12 40 159 41 21 41 2 4.7 72 3 4.0 5A . . . . . .. 33 4 11 203 14 6.4 12 3 2O 5 1 17 6A . . . . . . . 32 6 16 290 19 6. 1 1O O . . . . 38 8 17 7A . . . . . . . 13 17 57 131 36 22 46 2 4.2 147 7 4.5 12B . . . . . .. 31 22 42 322 72 18 51 1 1.9 161 32 17 7 . . . . . . . 46 14 23 237 19 7 4 35 3 7.9 47 O . . . . 12C . . . . . .. 8O 11 12 210 27 11 21 0 62 2 3.1 3D . . . . . .. 26 3 1O 22S 14 58 2O O 6 O 7E . . . . . .. 11 5 31 271 27 9 1 12 2 14 36 1 2.7 Crosses: Two sorts of crosses have been made at College Station, one involving the Dwarf Champion with a standard type and a Gulf State Market-Stone cross. Results of the first are presented in Table 51. All plats have a relatively small amount of pufi. Both third generation popu- lations have distinctly less puff than Dwarf Champion for the comparable harvest period. The record of the pollen parent of this cross was lost but it was one of two varieties, Bonny Best 33 or Earliana 1 or 45. All three of these lots had a somewhat higher percentage of puff in 1932 than Dwarf Champion 70 (Table 13). The second generation and both third generation populations segre- gated for the dwarf plant character, which is a simple recessive. The amount of puffing in dwarf and standard plants in the third generation plats is compared in Table 52. It will be noted that during the first harvest period the dwarf plants have more pufi in every instance, very much more in most cases. The values of chi square for this period are 25.98 for the population listed first and 22.66 for the one given below. This shows that the difference is highly significant. During the second period there seems to be less difference between the two growth types, chi square being 0.328 for the first and 4.84 for the second family. The Dwarf Champion had somewhat less puff than the pollen parent. If there is a linkage between genes for dwarfness and puffiness the F, plant select- ed as parent for the F3 must have been a cross-over, Table 53. Results of crossing Gulf State Market 73 x Stone 76. Based on total fruit. First harvest period Second harvest priod Per cent puffed Lot Year Genera- No. tion Data No. No. Data No. No. taken normal puffed taken normal puffed First Second 73 1932 P1 June . . . . . .. 671 214 July . . . . . .. 371 53 24 13 76 1932 P1 June . . . . . . . 165 133 July . . . . . . . 332 173 44 34 173 1933 F1 June . . . . . . . 314 34 July . . . . . . . 94 45 9 . 8 32 282 1934 F2 June-Aug. . 13 12 Oct.-Nov. . . 96 26 . . . . 21 416 1935 F3 June 27.... 8O 14 July 16..... 1 4 15 419 1935 Fa June 11 . . . . 26 9 July 12. . . . . 48 11 26 19 58 BULLETIN NO. 541, TEXAS AGRICULTURAL EXPERIMENT STATION Table 54. Results of crossing Stone 76 x Gulf State Market 73. Based 0n total fruit. First harvest period Second harvest period Per cent pufied Lot Year Genera- No. tion Data No. N0. Data No. No. taken normal puffed taken normal puffed First Second 174 1933 F1 June . . . . . .. 303 32 July . . . . . . . 1S6 34 .9.6 18 285 1934 F2 June-July.. 12 15 Oct.. . 6 1 423 1935 F3 July 6 . . . . .. 26 5 July 15. . . .. 2O 2 16 424 1935 Fa July 12..... 28 3 July 17..... 5 1 9.7 427 1935 F3 July 5 . . . . .. 20 13 July 17... .. 0 3 39 429 1935 Fa July 6 . . . . . . 34 4 July 15. . . . . 7 4 11 . . . . Total 1935 F3 July . . . . . . . 108 25 July . . . . . . . 43 1O 19 19 691 1936 F4 . . . . . . . . . . 44 7 . . . . . . . . . . 30 18 14 3S Table 5". Results of crossing Stone 9 x Gulf State Market 73. Based on total fruit. First harvest period Second harvest period Per cent puffed Lot Year Genera- o. tion Data No. No. Data No. No. taken normal puffed taken normal puffed First Second 9 1932 P1 June . . . . . .. 170 130 July . . . . . .. 233 97 43 29 73 1932 P1 June . . . . . . . 671 214 July . . . . . . . 371 53 24 13 175 1933 F1 June . . . . . . . 36 3 July . . . . . . . 37 21 7.7 36 287 1934 F2 June-Aug“ . 21 14 Nov . . . . . . . . 8 3 40 . . . . 431 1935 F3 July 1 . . . . . . 227 31 July 15..... 85 24 12 22 432 1935 Fs July8 . . . . .. 37 16 July 16..... 30 433 1935 F3 July 6 . . . . .. 108 12 July 17. . . .. 57 » 2 10 3 4 688 1936 F4 . . . . . . . . . . 46 7 . . . . . . . . . . 63 32 13 34 728 1936 F4 . . . . . . . . . . 5 0 . . . . . . . . . . 24 1O 29 741 1936 F4 . . . . . . . . . . 31 2 . . . . . . . . . . 29 24 6 1 45 Results of three crosses involving Stone and Gulf State Market are presented in Tables 53, 54, and 55. During the first harvest period the three first generation families had about the same amount of pufi as the best selection of Gulf State Market grown in 1933. During the second period two of the F1 populations had more puff than this selection, but no more than other strains. A selection of the Stone parent was not grown this season. Three lots of Early Stone were grown. These had consider- ably more puff than the crosses. During the 1935 season third generation selections varied from 10 to around 40 per cent, the latter figure being based on a small sample. The lower amount is about what was obtained from Gulf State Market during this period (No. 380 had only 5.0 per cent puff). The range during the second period was about the same for both. One lot of Early Stone had considerably more puff during the second harvest period. No satisfactory comparison is available for the fourth generation selec- tions. They appear to be better than most of the large-fruited sorts but no better than the best strains of these. During the winter of 1935-36 double crosses were made in the green- house between third generation selections of the two types of crosses dis- cussed above. The puffing data obtained in the field the following season are presented in Table 56. The amount of puffing in these is, in general, \ FACTORS AFFECTING THE AMOUNT OF PUFFING IN TOMATOES 59 Table 56. Results of double crosses involving four varieties—-College Station, 1936. Based on total fruit. First harvest period Second harvest period Per cent pufied Lot Parentage No. No. No. No. No. First Second normal puffed normal puffed 726 174 x 176 111 6 88 29 5 . 1 25 71S 176 x174 68 7 32 9 9.3 22 733 176 x 174 3S 5 30 9 13 23 737 176x 174 31 2 14 6 6.1 . . . . . . .. Total 176 x 174 134 14 76 24 9.5 24 724 175 x176 59 3 43 15 4.8 26 729 17S x 176 103 12 42 16 10 28 735 175 x 176 46 3 64 29 6.1 31 Total 17S x 176 208 _ 18 149 6O 7.9 28 712 176x 175 41 2 19 10 4.6 . . . . . . .. 716 176 x 175 68 6 S9 27 8.1 31 72S 176x 175 40 3 11 8 7.0 . . . . . . .. 727 176x175 30 1 11 2 3.2 . . . . . . .. 740 176 x 175 18 0 7 4 . . . . . . . . . . . . . . . . Total 176 x 175 197 12 107 51 5 7 38 less than that of the fourth generation selections of the two crosses grown this season. The range for the 12 families of double crosses for the first period is 3.2 to 13 per cent and for the second period 22 to 38 per cent puffed fruits. This increased amount of pufiing during the sec- ond harvest period is ascribed to the large amount of rainfall after May 20. Only two “large-fruited” varieties (Beauty of Lorain and Kan- ora) were within this range. In addition to the controlled crosses, several lots were grown from accidental crosses between large and small fruited types. The results secured during 1935 are presented in Table 57. A lot secured from Dr. T. M. Currence of the Minnesota Station has been included here be- cause of the rather small size of the fruit and the similarity in behavior to Table 57. Crosses with small-fruited types-—C0llege Station, 1935. Based on total fruit each harvest period. No. fruit No. fruit Per cent puff Seed Lot Year _ Data i Data parent No. grown taken Nor- taken Nor- mal Puffed mal Pufied First Second Minnesota . . . . .. 315 1934 June. . . . . 114 0 July-Aug. 24 4 0.0 . . . . .. Minnesota . . . . .. 406 1935 July 2. .. 57 4 July 16... 30 0 6.6 0.0 Dwarf Champion 349 1935 June 25. . 440 36 July 15... 264 14 7.6 5.0 Globe . . . . . . . . . .. 371 1935 July 5.... 37 0 July 17... l8 0 0.0 . . . . .. Marglobe. . . .. 392 1935 June 28.. 199 3 July 16... 140 1 1 .S 0. 7 Marglobe . . . . . .. 397 1935 July 5.... 90 9 July 17. .. 9 1 9.1 . . . . . . Gulf State Mkt.. 377 1935 July 7.... 420 16 July 17. .. 112 3 3.7 2.6 Stone x Gulf State Market. 430 1935 July 3. . .. 261 3 July 17. .. 183 O 1.1 0.0 crosses of large and small fruited sorts. The crosses are all second gen- eration populations, since in each case the F1 was discovered as a single plant with fairly small fruits and very little puff among a family with normal sized fruits and considerable puff. The uniformly small amount of puff obtained in these lots is quite striking. Even in the cases where 60 BULLETIN NO. 541, TEXAS AGRICULTURAL EXPERIMENT STATION Marglobe, which puffs badly, is the seed parent, less than 10 per cent of the fruits are puffed. Dominance of small fruit size was to be expected. During the 1936 season selected third generation families and crosses with a large fruited variety were grown. Of these populations lots 696 and 700 involving Globe and Marglobe (Table 58) had the smallest fruit Table 58. Crosses with small-fruited types-—College Station, 1936. Based 0n ' total fruit each harvest period. First Second harvest period harvest period Per cent Seed parent Lot puffed cross N0. No. fruit No. fruit Normal Puffed Normal Puffed First Second Dwarf Champion . . . . . . . . . . . . . . 695 156 0 121 13 0 9.7 Globe . . . . . . . . . . . . . . . . . . . . . . . . 696 446 1 242 1 0.2 0.4 Marglobe . . . . . . . . . . . . . . . . . . . . . 700 201 2 164 2 0.98 1.2 Gulf State . . . . . . . . . . . . . . . . . . . . 723 53 1 43 5 1.8 10 Gulf State . . . . . . . . . . . . . . . . . . .. 731 87 1 53 19 1.1 26 Stone x Gulf State Market . . . . . 704 65 6 39 0 8.4 0 (Gulf State Market x sm. fr.) x Bonny Best . . . . . . . . . . . . . 717 74 3 27 12 3.9 31 (Gulf State Market x sm. fr.) x Kanora . . . . . . . . . . . . . . . . 739 34 0 45 5 0 10 Kanora x (Gulf State Market x sm. fr.) . . . . . . . . . . . . . . . . 738 46 3 44 16 6.1 27 739 + 738 . . . . . . . . . . . . . . . . . . . . . . . . . . 80 3 89 21 3.6 19 and lot 717, the “backcross” to Bonny Best, had the largest, indicating a slight increase in proportion of puffed fruit with an increase in fruit size. Discussion: With a character as responsive to environmental condi- tions as tomato puff, slight hereditary differences will be entirely covered up where the lots compared are subjected to different growing conditions. Large genetic differences such as obtain between most of the small fruited varieties and Globe are evident for all ordinary field conditions, and per- haps might be under any conditions. Even among large fruited sorts, if environmental factors are neglected, there is little overlapping under field conditions between varieties such as Kanora and Marglobe. Such hereditary differences are the basis of a search for low puffing strains of commercial varieties and a breeding program to secure new varieties with a minimum amount of puff. Strains that have under 10 per cent of their fruit puffed as classified in this report will have prac- tically no loss on this account under commercial conditions. This is be- cause there are few if any severely puffed fruits where the proportion of abnormal fruits is low. No strain of Marglobe has yet been found with a reasonably low amount of puff. Considerable difference has been found among strains of Gulf State Market, but a strain satisfactory from this standpoint has not 'yet been found. The best strains of Bonny Best, Earliana, Stone, and a number of others are very promising. As with other characters, the crosses are based on securing a recombi- nation of factors. Several factors are obviously involved, the plan being to replace genes favoring puffing with those favoring normal development in case different loci are involved in different varieties. The selections of the FACTORS AFFECTING THE AMOUNT OF PUFFING IN TOMATOES 61 two original crosses between large-fruited varieties can not be considered better than the best strain of the parents involved. The first generation 0f the double cross does represent a marked improvement, Both selfed populations and crosses to new low-pufiing varieties will be grown to secure constant lines with little puff. ' The crosses to the small-fruited varieties have given populations with less puff than those from the above crosses, but they have the disadvan- tage of relatively small fruit. “Backcrosses” to new low-puffing large- fruited varieties are being made. Progress along this line probably depends upon crossing over between genes for defective fruit and those for fruit size. Results of the pufiing investigations thus far indicate that the best practical solution of the problem lies in growing only strains that are known to have a minimum of puffed fruit under ordinary field conditions rather than to manipulate the environment to reduce the amount of pufling. In considering the origin of differences among varieties as to amount of puff it should be pointed out that the garden tomato as now grown is vastly different from the wild types from which it originated. The Cherry tomato grows as an escape in Texas and is well adapted, in that it grows vigorously, sets fruit during the entire summer, and has no puff to speak of. The development of the modern large-fruited tomato from a similar wild parent took place in Europe and in the northern United States under climatic conditions different from those in the Southwest. It is not so surprising, then, that our present varieties lack the adaptability of their ancestors when grown under the conditions here, and that conditions that differ from the optimum obtaining where they were being evolved result in the defective development of a greatly modified fruit. The environ- mental conditions that favor puffing may thus be considered as deviations from the optimum for tomatoes as now genetically constituted. There was no opportunity during the development of the large-fruited sorts for selecting those factors or combination of factors that might have resulted in a tomato having both perfect adaptability to Texas conditions and an acceptably large fruit. It is possible that this ideal cannot he perfectly attained, but the wide variation observed among the different varieties and the evidence from the crosses suggest that this can be done. SUMMARY Tomato puff is a defect of the fruit, in which the seed-bearing tissue' develops abnormally, leaving a partially hollow fruit or one in which the cross walls have grown to fill the seed cavity. It was noted at this station as early as 1895. Defective fruits can be identified at a very early stage, although the abnormality is thought to develop later at times. The proportion of fruits affected varies widely (from 0 to 100 per cent) with variety and growing conditions, depending upon hereditary and en- vironmental factors. 62 BULLETIN NO. 541, TEXAS AGRICULTURAL EXPERIMENT STATION Under greenhouse conditions, when high temperature was not a factor, plants with low_available moisture had a smaller proportion of puffed fruits than plants with a large amount of available moisture. Such dif- ferences were greater for the first fruits harvested than for those har- vested later. The same relationship was found in only part of the irrigation experi- ments. \ Plants sprayed with Bordeaux had less puff than those sprayed with a mixture of Bordeaux and a heavy oil spray. This is interpreted as a moisture relationship since Bordeaux increases, oil depresses, transpira- tion. A general relationship Was found between amount of rainfall and pro- portion of fruits puffed. If the amount of rainfall is higher earlier in the season, the proportion of puffed fruits is higher during the first harvest period than later. When more rainfall occurs later, there is a general increase in the proportion of puffed fruits. ' Other factors, such as differences in varietal response to changes in available moisture, have been found to modify this expectation in certain instances. When maximum temperatures in the greenhouse exceeded 100°F; the percentage of puffed fruits for all water treatments approached or reached 100. During the 1934 season in the field at College Station, the high maximum temperatures are considered to be responsible for the higher proportion of puff than was obtained later in the season with much more available water but cooler weather. When maximum temperatures in the greenhouse remained below 100°F. there appeared to be a direct relationship between minimum temperatures and amount of puff. These did not get below 60°F. These influences of water and temperature were found to be effective chiefly during the early development of the fruit. For this reason the date of fruit setting must be known if the influence of environmental con- ditions is to be studied. It also follows that for a comparison between any two lots, only fruit setting at approximately the same time can be used satisfactorily. A comparison of plants grown in soils from northern and southern sources gives no indication that the freedom from puffing in the North is due to the presence of some minor element in soils of glacial origin which is lacking in soils in the South. Less puff was found in evervy case at College Station where a 6-12-6 fertilizer was added. Results on the more productive soils on the Lower Valley station were inconsistent. It is pointed out that a reduction in proportion of puffed fruit accompanying a fertilizer application might be through its influence on the amount of free water in the plant. FACTORS AFFECTING THE AMOUNT OF PUFFING IN TOMATOES 63 Certain fertilizer supplements such as the sulphates of magnesium and iron were not found to affect the proportion of puffed fruits materially at the Lower Valley station. No association was found between southern blight 0r blossom end rot and the proportion of puffed fruits. Hand pollinating flowers of Marglobe in the field reduced the amount of pufling. A relation between available pollen and amount of puff prob- ably explains the excessive amount of pufling when maximum tempera- tures exceed 100°F. While pollination is undoubtedly a factor in de- termining the amount of puffing under field conditions, it is not considered to be the dominant factor. A satisfactory comparison of fruits from different clusters of the same plant is difficult because they must necessarily set at different times and a change in environmental conditions may be expected. In spite of the important influence of environmental factors on puffing, varietal (hereditary) differences are found. The degree of difference that can be distinguished satisfactorily depends upon the amount of data and on the similarity of the environmental conditions affecting any two lots while the fruit is setting. The small-fruited varieties, with the exception of Pomodora, all have little or no puff. Ranked according to increasing tendency toward puffi- ness, they are Currant, Cherry, Plum, and Pear. Of the large-fruited sorts, those having oblate fruit with many locules puff less than those with globular fruit and few locules. Those with very large fruit having a tendency toward fasciation also have a high propor- tion of puff. Varieties of the Bonny Best type thus have been found to puff less than Globe and Marglobe. Low-puffing varieties include Kanora, Marketeer, and Success. Differences have also been found between strains of the same variety. Low-puffing strains include Bonny Best 710, Earliana 440, and Stone 661. Significantly more puff was observed among progeny of 17 individual plants selected for large amount of puff than from 17 plants from the same lots that were selected for low amount of puff. Several hereditary factors for abnormal fruit are evidently involved and appear to be, for the most part, recessive. Crosses between large and small-fruited sorts are much nearer the latter in fruit size and puffing. Selections from crosses between commercial varieties have about the same proportion of puff as the best parent. Crosses of two distinct third generation selections, involving four varieties, have a low amount of puff. This is expected to show segregation. In crosses between dwarf and standard types the dwarf segregates in the third generation had more puff than the normal in spite of the fact that the dwarf parent appeared to have less puff than the standard. The use of varieties and strains, selected for their ability to produce normal fruit under southern conditions, and the development of new low- puifing varieties by breeding would seem to be the only practical solution of the problem. 64 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 2s. 24. 25. 26. BULLETIN NO. 541, TEXAS AGRICULTURAL EXPERIMENT STATION LITERATURE CITED Auchter, E. C. 1935. Fruit and Vegetable Crops and Diseases. Report of the Chief of the Bureau of Plant Industry, 1935214. Bailey, L. H. 1891. Experiments in the Forcing of Tomatoes. Cornell Univ. Agr. Exp. Sta. Bul. 28 Crist, J. W. 1926. Effect of Nutrient Conditions on Colloidal Properties 0f Certain Vegetable Crops. Mich. Agr. Exp. Sta. Tech. Bul. No. 74. Fisher, R. A. 1930. Statistical Methods for Research Workers. Ed. 3. London, Oliver and Boyd. Fletcher, S. W. and O. I. Gregg. 1907. Pollination of Forced Tomatoes. Mich. Agr. Exp. Sta. Spec. Bul. 39. Friend, W. H. 1931. 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