II! I,‘ ABSTRACT morons ASSOCIATED WITH mmnonop SOLUBLE soups IN mm mm or THE oonoonn GRAPE, m M L. Hy Darrell Sparks Soluble solids of dbncord grapes in Michigan vary widely from.yesr to year, but the fruit from some vineyards is consistently low or high regardless of seasonal.variation. This indicates that "permanent" factors are present within a vineyard which affect soluble solids in a consistent manner. Experiments were conducted in 1962, 1963, and.l964 to determine the effect of various levels of shade and time of shading on the production of soluble solids. In 1962, one-half of the clusters per vine was.removed to study increased leaf to fruit ratio singly and in combination with shade. The effect of shoot tipping (to stop terminal shoot growth) was also studied. A vineyard survey was conducted in 1962 and 1963 in southwestern Michigan to determine vineyard and cultural practices associated.with variation in fruit soluble solids. Leaf petioles, shoot tips and berries were analyzed for nitrogen, phosphorus, potassium, calcium, magnesium, manganese, iron, copper, boron, and zinc. Soil samples were rated as to texture and analysed for available phosphorus, potassium, calcium, and magnesium; cation exchange capacity; percent saturation of potassium, cal- cium, magnesium; and percent base saturation. Foliage density was visually estimated and notes were made as to row direction, soil management, spacing, trellis height, and clusters per vine. Tho nitrogen studies were initiated in 1963 and 196% to determine the effect of nitrogen on production of soluble solids. One study involved Darrell Sparks - 2 growers' vineyards under a wide range of conditions. One pound of ammonium nitrate was applied per vine and number of shoots per vine, growth per shoot, rate of growth and days of shoot growth were recorded. Foliage den- sity was estimated and leaf area per pound of fruit calculated. A second study was conducted at the Sodus Herticultural Farm. The vines were bal- ance pruned and there was little variation in soil or general vine condi- tion. One pound of ammonium nitrate in combination with various levels of sawdust was applied per vine. The weight of pruned material per vine was recorded in the winter of 1963. In both studies, yield and number of clus- ters per vine were recorded and soluble solids samples were taken at harvest. Shading lowered production of soluble solids; whereas, shoot tipping had no effect. Thinning clusters increased soluble solids only if the vines were not shaded. This indicated the leaf to fruit ratio was limiting solu- ble solids, but was dependent on the exposure to sunlight. The survey revealed that the major factors associated with low soluble solids were: (1) shading due to high foliage density, and (2) low leaf to fruit ratio. There was a negative correlation of soluble solids with fo- liage density and clusters per vine, and between soluble solids and soil cation exchange capacity. The correlation was positive between soluble solids and square feet of soil surface per vine. With added nitrogen in commercial growers' vineyards, variations in leaf area per pound of fruit and foliage density accounted for a high percentage of the total variation in soluble solids. The effect of fo- liage density on soluble solids was greater than the leaf area per pound of.fruit. Growth per shoot, rate or days of growth were not inversely related to soluble solids. Thus, the effect of foliage density on solu- ble solids was not due to growth pgg,gg, That the effect of foliage Darrell Sparks - 3 density was due to shading was indicated by altering the trellis to pro- vide better exposure, resulting in higher soluble solids. Foliage den- sity had less effect in 1963 than in l96h due to differences in climatic conditions. Applications of nitrogen had no effect on soluble solids, yield per vine or growth in the growers' vineyards. However, at the Sodus Farm, applications of nitrogen increased growth when measured as pruned weight removed. There were more buds per vine in 1964 with greater foliage density and lower soluble solids. The difference was probably due to balanced pruned vines and less soil variation at Sodus. ACKNOWLEDGMENTS Appreciation is expressed to Dr. R. P. Iarsen for his assistance and guidance throughout this investigation, and for constructive criti- cisms and suggestions in preparation of the manuscript. Appreciation is also expressed to Drs. A. L. Xenworthy, C. M. Harrison, H. D. Foth, H. J. Bukovac and J. Hull, Jr. for their advice and guidance during the course of this investigation. The author is grateful to Drs. A. L. Kenworthy and D. R. Dilley for use of various laboratory facilities, to Dr. J. D. Downes for ad- vice concerning statistical problems, and to the many fellow graduate students who helped collect the data under often diverse conditions. Acknowledgment is made to Dr. A. E. Elser, Messrs. Bruce Beard and John Bouwkamp for many discussions. Grateful acknowledgment is extended to the growers who made their vineyards available for the survey studies, and to the Michigan grape processors who provided the funds through the Concord Grape Research Committee that made the studies possible. Special graditude is expressed to Miss.Junette M. Merrill. Tb my parents Mr. and Mrs. Fred Sparks whose—determination'willsalwqys be a source of inspiration. FACTORS ASSOCIATED WITH VARIATION OF SOLUBLE SOLIDS IN THE FRUIT OF THE CONCORD GRAPE, VITIS LABRUSCA L. By Darrell Sparks A THESIS Submitted to Michigan State University in partial fulfillment of the requirements for the degree of DOCTOR.OF PHILOSOPHY Department of Horticulture 1965 ,L, \ TABLE OF connmrs 3 mmmcnw O O O O O O O O O I O O O O O O O O O O O O O 0 LI mm RHIW O O O O O O O O O O O O O O O 0 O O O O O Apparent Relation of Fruit Growth and Sugar Ac 0mm man 0 O O O O O O O O O O O O O O O O O 0 Climatic Factors Associated with Variation of Soluble Bonds or m‘p.’ I O O O O O O O O O O O O O O O O 0 Cultural Conditions and Practices Associated with V‘ri‘tion Of SOlnbl. Sand! 0 O O O O O O O O I _ 0 Conclusions from the Literature Review and Basis for subaoqmt Stmos. O O O O O O O O 0 mm AND mmm O O O O O O O O O O O O I. ShadingStudies.......... II. Survey, 1962 and 63 . . . . . . . . III. Nitrogen Study - Growers' Vineyards IV. Nitrogen Study - Sodus . . . . . . RESULTS. 0 O O O O O O O O O O O O O O O O O O I. Shading Studies . . . . . . . . . . II. Survey, 1962 and 63 . . . . . . . . III. Nitrogen Study - Growers' Vineyards IVe Nitrogen Study - Sadu‘e e e e e e e mSCUSSION O O O O 0 O O O O O O O O O O O O 0 Effect of Shading and Foliage Density on C O O O O O O O Soluble O O O O sand, 0 O O C O O O O O O O O O O O O O O O O 0 Effect of variation of Leaf Area per Pound of Fruit on Salubla &lids . C C C O . C C . O C O 0 . C . Effect of Nitrogen on Fruit Soluble Solids . . . . . . Effect of Soil Texture and/or Cation Exchange Capacity onh‘uitSOIUblasahdSe e e e e e e e e e e e Variation of Fruit Soluble Solids Between Years SWe O O C O I O O O O O O O O O O O O O O O O O O 0 REFERENCES CITED . . . . . . O O O O O O O O O O O O I 0 “Pmmx O O O O 0 O O O O O C O O O O O O O O O O O 0 0 iii 0 Page lb 16 16 20 22 26 26 26 b9 52 52 55 56 58 58 . '66 7O TABLE 2. 3. 9. 10. 11. LIST OF TABLES Variation of soluble solids between years and Vineylrdle e e e e e e e e e e s e e a e e e e e e e e Effects of shading, shoot tip removal and cluster thinning on soluble solids, yield per vine and weight per cluster. Shading studies, 1962 . . . . . . Effect of shade and time of shade application on soluble solids, yield per vine, berries per cluster and berry weight. Shading studies, 1963 ‘nd a e e e e e e e e e e e e e e e e e e e e e e e Effect of leaf exposure within vines on soluble solids. Sh‘ding Stud108, 1964. e e e e e e e e s e e e e e e e Relationship of soluble solids to nutrient content of petiole, shoot tips and grape berries. Survqy Vinlytrdl, 1962 and 63 e e e e e e e e e e e e e e e e Relationship of soluble solids and.various soil pro- perties. Survey vineyards, 1962 and 63. . . . . . . . Relationship of soluble solids to various soil pro- perties, petiole potassium and vigor. Survey '1DQyIrdl, 1962e e e e e e e e e e e e e e e e e a e e Relationship of soluble solids to vigor, foliage density, clusters per vine and cultural practices. Survey vineyards, 1962 and 63. . . . . . . . . . . . . Effect of nitrogen application on petiole nitrogen, yield per vine, clusters per vine, berries per cluster, weight per berry, leaf area per pound of fruit, shoot length, foliage density and soluble solids of Concord grapes. Nitrogen study - growers' VinCy.rd., 1963 ‘nd 6“ e s e e e e e e e e e e e e e e Relationship of growth and leaf area per shoot and solu- ble solids to petiole nitrogen. Nitrogen study - growers' vineyards, 1963 and 61+. . . . . . . . . . . . Relationship of soluble solids to foliage density, growth, yield per vine and leaf area per pound of fruit. Ni- trogen study - growers' vineyards, 1963 and 64 . ... . Relationship of foliage density to leaf area per shoot and shoots per vine. Nitrogen study - growers' vine- y‘rda, 1963 ‘nd 6“ s e e e e e e e e e e e e e e e e e iv Page 27 28 29 31 32 33 35 “1 #2 LIST OF TABLES - continued TABLE 13. 1M. lje 16. 17e 18. 19. Variation of soluble solids, foliage density, leaf area per pound of fruit and per shoot, yield per vine, number of shoots, rate of shoot growth and days of growth. Nitrogen study - growers' vine- y‘rd‘,l%3md6ueeeeeeeeeeeeeeeee Phonological and climatic variation. Nitrogen study - growers‘ vineyards, 1963 and 64 . . . . . . . . . . Effect of nitrogen application on petiole nitrogen, yield per vine, clusters per vine, berries per cluster, weight per berry, number of buds, pruned ‘weight, foliage density and fruit soluble solids. Nikos“ study - Sad”, 1963M6ue e e e e e e e e Effect of thinning clusters on petiole nitrogen, yield per vine, clusters per vine, berries per cluster, weight per berry, pruning weight, buds per vine and fruit soluble solids. Nitrogen study - Sodus, 1963. Effect of trellising on soluble solids, yield per vine and weightgper berry, 1964. . . . . . . . . . . Seasonal variation of soluble solids according to £011“. dmaityo O O O O O O O O O I O O I O O O O 0 Relationship of soluble solids to foliage density. clusters per vine, cation exchange capacity, soil texture and square feet per vine. Survey vine- yards,l9628nd63.......o......... Page #8 49 50 50 6O 63 FIGURE 1. 2. LIST OF FIGURES The relationship of leaf area to the length of the contrtlvtin,l963................. The relationship of leaf area per shoot l.hgth,1%3eeeeeeeeeeeeeeeeeeee The relationship of soluble solids to cation exchange capacity. Survey vineyards, 1962 and 63. . . . . . to shoot The relationship of soluble solids to soil texture. Survey vineyards, 1962 and 63 . . . . . . . . . . The relationship of soluble solids to square feet of soil surface per vine. Survey vineyards, 1962 and3...................... The relationship of soluble solids to number of clusters per vine. Survey vineyards, 1962. . . . The relationship of soluble solids to foliage density. Survey vineyards, 1963. . . . . . . . . The relationship of soluble solids to leaf area per pound of fruit and foliage density. study - growers' vineyards, 1963 and 6h Nitrogen Page 23 2a 36. 3? 38 39 #6 INTRODUCTION Grapes constitute an important segment of the fruit industry of Michigan. Most of the approximately 50,000 - 60,000 tons normally produced on 22,000 acres in southwestern Michigan are processed as juices, wine and other products. The predominant variety is Concord (Elias.Lssaaaaa.L.). A major problem associated with production is variation of fruit soluble solids. Data from 72 vineyards obtained over a five year period, 1957-61, by a Michigan processor revealed soluble solids varied widely from.year to year with some vineyards being consistently high or low regardless of seasonal variation, Table 1. Thble 1. Variation of soluble solids between years and vineyards. Soluble .__________._E..._IIIP so lids class 1957 195 1959 .1960 1961 Soluble solids - f High 17.4 16.5 17.6 16.7 16.“ Interlediate 16.5 16.1 17.0 16.0 16.0 low' 15.8 15.6 16.9 15.6 15.3 Mbans 16.7 16.2 17.2 16.1 16.0 The variation of soluble solids between vineyards is of economical importance, especially during years of relatively low average soluble solids. In such years, the soluble solids in the grapes from consistently low vineyards may be below the commercially acceptable minimum of 15.0 percent. Variation, during years of a relatively high average, is also of economical importance since the market price increases. with the solu- ble solids content, in the range of 15.0 to 18.0 percent. The fact that some vineyards are consistently high or low in solu- ble solids, indicates that there are "permanent" factors within vine- yards which influence soluble solids. LITERATURE REVIEW Introduction Percent soluble solids in grape juice is used as an indirect measure of the total sugar content. The measurement is usually made with a refractometer or a Belling or Brix hydrometer. All three methods give essentially identical results (69). The relationship of soluble solids and total sugars is usually assumed to be linear. In a b year study involving about b0 varieties of American bunch grapes and 208 observations, the correlation coefficient of total sugars and total soluble solids was .925 (66). A similar correlation (.917) was found for the Concord variety. This correlation was cal- culated from data reported in a 3 year study by Kertesz (32). The slope of the line for regression of total sugars on soluble solids was .957. These correlations for the grape are in close agreement with the correlation (.923) found for the sour cherry (60). The sugars in grape juice are predominantly glucose and fructose with small and variable amounts of sucrose (h, 1h, 67, 70). Since sucrose has been found (58) to be the translocated sugar in the Concord variety, glucose and fructose presumably result from its hydrolysis. The site of hydrolysis appears to be in the berry since invertase activity has been detected in extracts of ripe berries (h). Winkler (70) has assumed that glucose predominates during the growth of the berry; at maturity, the preportions of glucose and fructose are about equal, and in over-ripe berries fructose is the major sugar. Apparent Relation of Fruit Growth and Sugar Accumulgtion The growth curve of fruit from seeded and seedless varieties of American (12, #3) and European (18, 71) grapes, like stone fruits (20, 22, 39, #0, 60), is a double sigmoid curve. This curve is usually di- vided into three distinct periods of growth: period one, with a rapid rate of berry enlargement; period two, with only a slight rate of growth; and period three, with an intermediate growth rate. In seedless grapes the second period is sometimes not as distinct as in seeded varieties, but it becomes very distinct if growth is plotted as rate (18). The level of sugars in the grape berry remains relatively low and constant until the second period of growth. At this time the rate of sugar accumulation rises sharply, almost on a certain day, and in some varieties reaches a maximum rate within 10 days. After the rate of sugar accumulation begins to increase, the third stage of growth becomes evident. The maximum growth rate of the third period is preceded a few days by the maximum rate of sugar accumulation (9, 18, 71). On the basis of the correlation of sugar accumulation and fruit growth during the third period, Coombe (18) and Winkler (70) have sug- gested that the third stage of growth is due to the accumulation of sugar followed by the influx of water in response to diffusion pressure deficits. This suggestion is supported by the work of Winkler and Williams (71) who found that the insoluble solids of the berry remained approximately unchanged during the third period. Also, Crane and Brown (20) found that 72 percent of the total dry weight of the fig fruit, 89 percent of the total sugar content, and 60 percent of the total mois- ture was accumulated during the third stage. 5 Various hypotheses have been prOposed to explain the decrease in fruit growth during the second period. These, in general, have favored a competition between the seed and the pericarp or between the fruit and other parts of the plant. The hypothesis of competition between seed and pericarp is sup- ported by Nitsch (L2) and by the correlation found between embryo abortion and earliness in stone fruits (60). However, as has been pointed out by Winkler (39), this hypothesis does not account for the growth of seedless fruits. Dorsey and MbMunn (21), working in Illinois, suggested that the second growth stage of the peach fruit may be due to competition from growth in the tree and not primarily to food substances used in forming the stone. Later (22) these workers reported that shoot growth acceler- ated during the second period of fruit growth. However, the reported change in rate was not large, and their data was inconsistent. Also, Lilleland (38), in a similar study with peaches, found that shoot growth was over before the second period began. Furthermore, a wide variation in yield did not alter the growth rate of the second period. Winkler and Williams (71), working in California, found that shoot growth and trunk circumference of the grape had practically ceased by the inception of the second period. Also, the storage of starch and sugar in the canes continued through the major period of berry growth. In addition, removal of 90 percent of the original leaf area at the in- ception of the second period of growth did not prevent the third period, deepite renewed vegetative growth. They stated that these results pointed to an increasing supply of available nutrients rather than to a sudden decrease. These workers concluded that whatever the nature of the slow berry growth during the second period, it did not appear to be the result of nutritional competition within the vine itself. Winkler (70) decided, on the basis of the rapid accumulation of sugar in the fruit (9, 18), that the rate of movement is too rapid to result simply from.a change in competition for carbohydrates. Lilleland (39), in California, has shown that the time the apricot fruit remained in the first period and the time to maturity appear to be independent of shoot growth. Eb increased the night temperature of the fruit and shoots on four percent of the tree, and the remainder of the tree served as a control. An increase in night temperature of about 20 degrees for eight weeks, from March 19, shortened the duration of the first period by 22 days. The fruit ripened 21 days earlier than the control. There were no differences in final fruit size, but there was an advance in shoot growth. In another experiment shoot growth was not advanced, and the fruit emerged from the second period 28 days earlier than the control. Eb concluded that shifting the periods of growth of individual fruits, independent of the time of maximum vegetative growth, minimized the probability of any inter-rela- tion between the initiation of the second period of fruit growth and the time of maximum shoot extension. He further concluded that if the se- . cond period of fruit growth is due to competition, that competition comes more likely from within the fruit than from.other parts of the tree. He explained that the growth of the fruit during the first period is a re- sponse to its environment. Thus, synchronism of all the fruits on a tree can be ascribed to their response to the same identical environment. Tukey (61), in Pennsylvania, increased the average diurnal tempera- ture of the Concord grape by altering the night temperature for the 13 days after full bloom. The rate of berry enlargement was increased, up to a limit, in proportion to the temperature increase. At harvest the size of the berry and its soluble solids content were increased in the same proportion. Similarly, Clore and Bryant (16) associated ab- normally high minimum temperatures in May and June with high soluble solids at harvest. Climati ctors Associated with V riat on of Soluble Solids of Grapes Amerine and Winkler (3) concluded, from a study of climatic data, that temperature was the only predominant climatic factor influencing the quality of wine. Winkler (69) found that the effect of temperature, expressed as a summation of degree days above 50 degree F, can be used to predict the maturity of table grapes in California with a deviation of i 2 days. Mhturity was measured as degrees Belling. The California grape industry was divided into 5 geographical regions based on the amount of heat received from April to October (3). The regions range from 2,500 degree days in Region 1 to more than h,000 in Region 5. Late maturing varieties are not recommended for Regions 1 and 2 since they fail to ripen in cool seasons. Between regions, the time of maturity is inversely related to the rate of accumulation of degree days. For example, the Thompson Seedless variety develops from bloom to a maturity of 18 degrees Belling in the. Coachella Valley - a hot desert region - in approximately 68 days (69) and the ripening period is about 21 days. At Ibvis, a moderately warm region, 90 or more days are required, and the ripening period covers 30 days. waever, in both regions 2,000 degree days, i 2 days, are required for this variety. Caldwell, in New York, (10) reported in a five year study involving 66 varieties of American grapes, that the climate has a marked effect on the sugar content during a particular year. He considered that the effect was masked, but that the dominant factor was the amount of sun- shine received during the period, March to September. The years of maximum sunshine during this period were associated.with maximum or next-to-maximum sugar content of the Juice in a majority of all varie- ties; the years of minimum sunshine had the lowest or next-to-lowest sugar content, and the years of intermediate sunshine had intermediate sugar content. However, his results were confounded to some extent with sampling dates. Partridge (46),working in Michigan, reported that the average summer temperature had a marked effect on the sugar content and quality of the grape. He considered that the variations in temperature due to differences in elevation, character of the soil, direction of the slope, and protection from the wind were enough to account for the lo- cal success or failure of vineyards in doubtful zones of production. He concluded from temperature records and other data that the Concord variety appeared to require an average mean temperature of at least 65.5 degrees F from May to September and a growing period of more than 160 days for successful production. In thhington (57) the Concord grape is reported to require at least 1,900 heat units from full bloom to produce a juice with a Brix of 16 or better. In Arkansas (30), at least 2,500 degree days are con- sidered to be necessary for 16.5 percent soluble solids. However, Shaulis and Robinson (5%) reported that heat summation units are less likely to be useful for the Concord variety in New York than has been found in California for vinifera grapes. But they concluded that varia- tions between seasons affect the date of maturity (16 degree Brix) more than pruning severity or trellis height variations. Wbrkers in washington (16) reported that the maturity of Concord fruit is determined not only by the total heat units but also by the period during the growing season when the most favorable temperature occurs. These workers associated abnormally high minimum temperatures in May and June with early shoot and leaf growth and advanced maturity. That the optimum temperature may vary with time in the Concord grape is supported by the work of Tukey (61). He found that the Opti- mum diurnal temperature for berry growth decreased with time during the 13 days following full bloom. Also, Brown (10, 11), working in Calfornia, found that the apparent efficiencies of different temperatures in the development of the apricot fruit varied widely with increasing tempera- ture. The time of harvest of the apricots was predicted, with a maximum deviation of 3 3 days, by use of the number of hours in various tempera- ture classes during the #2 days following full bloom. Cultural Conditions and Pgactices Associated with Variation of Soluble Solids According to Winkler (70), operations (girdling, limiting water, etc.,) that cause the vines to slow down or cease growing will tend to hasten ripening after the fruit reaches the ripening stage. A limited supply of nitrogen will cause the vines to cease growth early, tending to advance ripening, and applications of nitrogen,which cause the vine growth to continue actively, will delay fruit ripening. Also, Bukovac gt_gl_(13) 10 suggested that vigorous vine growth late in the season may be responsible for slow color develOpment and low sugar content of grapes. Other workers (48, 52, 62) have attributed low soluble solids to vigorous vine growth. However, yield, which usually in- creases with vigor (l, 8, as, 50, 52) has also been found to be inversely related to soluble solids (10, 26, 27, 19, 51, 65). Partridge (#8) found that the inverse relationship between yield, in the Concord grape, and soluble solids was apparent whe- ther a sub-division was made based on vigor or whether the popula- tion was considered as a whole. There was no definite relationship between soluble solids and vigor when vines of equal production but varied vigor were grouped. Partridge concluded that the apparent in- verse relationship of soluble solids with vigor was apparently due to the lower yield of the weak vines. However, in another study involv- ing the Campbell Early grape, there was no consistent relationship between soluble solids and vigor or yield (47). Shaulis, after considering the relationship of soluble solids, vigor and yield, concluded that soluble solids data without yield and vigor data are of limited value (52). Upshall and Van Harrlem (62) reported that high vigor Concord vines had lower soluble solids than did low vigor vines although the latter vines produced a slightly greater yield. Part of the difference in vigor was ascribed to five consecutive years of heavy pruning. These workers suggested that over pruhing strong vines may reduce both the quality and quantity of the fruit. Shaulis and Robinson (5h) found that pruning severities of 20 + 10, ll 30 + 10, and #0 + 10‘ did not appreciably affect maturity over a period of # years. However, with the lightest pruning level, there was a tendency towards delayed maturity. Yield increased with decreasing pruning severity. Kimball and Shaulis (33) found, in a four year study, that soluble solids decreased slightly as pruning severity was decreased from 20 + 10 to 65 + 10. Yield increased with increasing number of buds. Iarsen (36) found that spur pruning of 30 + 10 and conventional pruning of 15, 30 and 45 + 10 did not affect yield or soluble solids. Partridge (#7) found that soluble solids, when taken from vines with equal yields, increased with pruning severities from 60 to 30 buds per vine. Winkler (68) working with the vinifera grape in California, found that yield increased as pruning severity decreased from spur to cane pruning. Non-pruned and cans pruned vines on which the crop was con- trolled by thinning, had a more abundant supply of available carbohydrates than conventionally spur pruned or severely spur pruned vines. With some varieties the lower available carbohydrates, due to increased pruning severity, were associated with low pollen germination, shot berries, and straggly clusters. The differences in carbohydrates were attributed to differences in number of leaves and the length of the time during which the leaves were active. Pruning not only reduced the total weight of leaves per vine, but delayed the time of maximal leaf area beyond mid— summer. Winkler concluded that controlling the crop entirely by thinning, with no pruning, although uneconomical, would produce the largest crop with * The first figure, i.e. 20, 30, or #0 refers to the number of buds left on a vine for the first pound of one year old wood removed by pruning; the second figure, 10, indicates the number of buds left for each addition- al pound removed. 12 a high sugar content. He explained this would result in a large in- crease in the number of leaves early in the season resulting in an improvement of the nutrition of the flowers. He found a more economi- cal compromise was to cane prune with flower cluster thinning. This resulted in yields equal to or greater than conventional spur pruning and with a higher sugar content. workers generally agree (7, #6, 50, 57, 70) that grapes have a higher sugar content when grown on sandy soils than on "heavy" soils. The delay in maturity on heavier soils is generally attributed to ”stronger" vine growth. The fact that heavy soils tend to produce high vigor vines is reflected in the high positive correlation found for growth, measured as pruning weight, and soil organic matter (1, 50), total nitrogen, available moisture capacity, capillary porosity, clay and silt content and total cation exchange capacity of the soil (1). All of these factors often increase as soil texture changes from a sand tochw. Snyder and Brannon (57) suggested that although extremely light soils present problems in maintaining soil fertility and soil moisture, they may be very desirable in areas where total heat units are low. Hendrickson and Veihmeyer (29), working in California, found irrigation resulted in lower soluble solids in one year out of seven. This effect occurred the second year of treatment and was associated with increasing vigor and a 30 to #0 percent increase in yield. Other workers in California (63) found that irrigation did not consistently affect the sugar content of the fruit. Research, in Arkansas, showed that irrigation of one inch per week delayed maturation (30). However, the delay was slight as indicated 13 by difference in soluble solids. These workers did not report any effect of irrigation on yield or vigor. In Arkansas (19), applications of 30 pounds of nitrogen per acre for eight years did not affect the sugar content of grapes. workers in California (17) reported that rates of over #0 pounds of nitrogen per acre reduces color development and delays maturity by a few days. firtridge (#8), found, when comparisons were made between vines of approximately equal production, that addition of 35 pounds of nitrogen per acre the first year of treatment had no effect on soluble solids, but reduced soluble solids the second year of the treatment. He did not re- port any effect on vigor. In Ohio (8) applications of 0, #0 and 80 pounds of nitrogen per acre for eight years did not have a consistent effect on soluble solids. However, the soluble solids content of fruit from cultivated vines was consistently higher than fruit from mulched vines. The difference in soluble solids was attributed to the high nitrogen status of the mulched vines as evidenced by weight of prunings removed and leaf petiole ni- trogen. It was suggested that a higher level of soluble solids can be anticipated if petiole leaf nitrogen, in early July, is maintained in the range of .85 to 1.30 percent rather than above this range. In gener- al, however, the data showed that the greatest rate of decrease in solu- ble solids was within the range of .85 to 1.30 percent petiole nitrogen. Beyond 1.30 percent petiole nitrogen, soluble solids appeared to level off. Shaulis (52) found that 32 to 6# pounds of nitrogen per acre, for five years, was associated with lower soluble solids in proportion to l# the nitrogen applied. However, since yield and vine vigor increased in the same prOportion, he concluded that the data offered no evi- dence concerning the effects of fertilizer on the soluble solids content of the grape berry. low soluble solids have been associated with potassium defi- ciency (17, 35), but applications of potassium in vineyards having adequate potassium (l7, 19, 36, ##) have not affected soluble solids. However, Partridge found (#8) that vines which received potassium in combination with nitrogen produced higher soluble solids than nitrogen alone. Applications of phosphorus (l7, l9, #8), magnesium (36) and calcium (#8) have not been associated with variations in soluble solids. Shaulis and Robinson (5#) found that low trellised (# feet) grapes matured more slowly than did high trellised (7 feet) grapes. They suggested that the delay in maturity may have been due to shading of the foliage and thus keeping fruit cooler. A second suggestion was that the delay was due to the inferior leaf exposure on the low trellis. Kimball and Shaulis (33) found that soluble solids increased in proportion to spacing if vines of equal vigor were compared. They con- cluded that delayed maturity of large crops in large vines is dependent in part on the inadequate exposure of the large leaf surface. Conclusions from the Literature Review and Basis for Subsequent Studies Variation of the climatic environment, especially temperature and/ or light intensity, appears to be the most important factor responsible for variation in soluble solids between years. Seasonal temperature 15 and/or light intensity variations appear to alter the rate of fruit development and shoot growth. Many factors have been suggested as responsible for variation of soluble solids between vineyards within a given year. Usually these factors affect soluble solids by altering vigor and/or yield. However, these two factors usually vary together. The suggestion has been made that the effect of vigor on fruit soluble solids is due to competition for available carbohydrates and in one case to shading. Experiments were initiated to alter vigor, yield, and light intensity and to observe the effects, singly and in combination, on soluble solids production of the Concord grape. Also, vineyards were surveyed to determine the relative importance of various re- ported factors on soluble solids production. MATERIALS AND METHODS I, Shading Studies The primary purpose of this experiment was to determine the effect of shading during various parts of the growing season on soluble solids production. Secondary objectives were to determine the effect of reduced yield (thinning clusters) and shoot tip removal on soluble solids production. The shoot tips were removed in an attempt to check vegetative shoot extension. Pzgcedure: The experiment was conducted for three consecutive summers, 1962, 1963 and 196#, at the Horticulture Farm, East Lansing, Michigan. In 1962, a split-plot design was used with shading as the main plot and shoot tip removal and thinned clusters as the sub-plot treat- ment. The experiment was replicated four times with nine vines per replicate. Two weeks after full bloom (June 20) the total number of clusters per vine were counted and one-half of them were removed from designated vines. On August 15, the shade treatments, consisting of no shade, 30 per- cent shade, and 50 percent shade were applied for the five weeks preceding harvest. woven saran panels were placed over a previously constructed "cradle” so that each panel covered three vines as a modified umbrella, which was one foot above the vines, two feet wide, and dropped five feet along each side. Also, on August 15, approximately six inches were re- moved from the terminal portion of each shoot on designated vines. A soluble solids sample was taken from each vine at harvest, Sep- tember 20. The sample consisted of four apical berries from 16 basal clusters. Percent soluble solids of the expressed juice was determined 16 l? with a Zeiss hand refractometer immediately after collection. Yield records were obtained at harvest. In 1963 and 196#, the time of shade application was.the main plot and percent shadinngas the sub-plot treatment. The experiment was replicated twice with 18 vines per replicate. At full bloom the shade treatments, as described, were applied for either seven weeks following full bloom or later for the seven weeks preceding harvest. Soluble solids samples, consisting of 100 random berries per vine, were taken at harvest, September 26, 1963 and September 2#, 196#. The samples were held at O°F until fresh weights of the berries and percent soluble solids determinations were made. Yield and number of clusters per vine were recorded at harvest. A comparison was made in 196# of fruit soluble solids from fruit on exposed shoots versus shaded shoots on the same vine. There were seven shoots per treatment, and yield per shoot was recorded On September 2#, 196#. II. Surve l 2 and 6 A survey of Concord vineyards in southwestern Michigan was con- ducted during the summers of 1962 and 1963 to determine factors associ- ated with variation of soluble solids between vineyards. 'Procedure: In the spring of 1262, 100 ton vine plots were selected for study in van Enron and Berrien Counties. The plots were selected in vineyards with variable soluble solids records over the year. Two plots were generally selected per grower. These plots usually 18 differed in some aspect such as vigor, fruit soluble solids during past years, soil texture, row direction, trellis height, or soil management. Vine vigor was numerically rated from 1 to 5 by visual observation. Vines with very low vigor and those with high vigor were rated 1 and 5, respectively. Trellis height and spacing between vines were measured. Square feet of soil surface per vine was calculated as the product of spacing within and.between rows. Cubic feet per vine was calculated as the pro- duct of square feet of soil surface and trellis height. During mid-July, the number of clusters on five vines per plot was recorded and a soil, petiole and shoot tip sample was taken from each plot. Soil samples were taken from the surface soil to a depth of six to eight inches. Two cores of soil were taken, one from each side of the vine, at an angle of about #5 degrees to the row and about one foot from the trunk. The cores were thoroughly mixed and one-half pint was saved for analysis. The soil samples were analyzed by the Soil Testing Laboratory of the Soil Science Department for pH; available phosphorus, potassium, calcium, magnesium; cation exchange capacity; percent saturation of potassium, calcium, magnesium; and percent base saturation. The labora- tory also rated the samples from one (clay loam) to five (sand). Per- cent organic matter of the soil was determined by combustion (23). Petiole samples, consisting of 80 petioles, eight per vine, were taken from the most recent "mature" leaves on fruiting shoots. Shoot tip samples of 30 shoot tips, three per vine, were taken at random. The length of the shoot removed ranged from four to ten inches depending on the number of immature leaves. The petioles and shoot tips were free 19 of insect, disease, and mechanical injury. After sampling, the petiole and shoot tip samples were dried at room temperature for two weeks, then dried at 17u°r for 72 hours and ground in a Wiley mill.with a 20 mesh screen. The samples were analyzed for 11 nutrientwelements by the Plant Analysis laboratory in the Department of Horticulture. Potassium determinations were made with a flame photometer, nitrogen by use of the Kjeldahl method, and.caloium, magnesium, phosphorus, manganese, iron, copper, boron, and zinc by photoelectric spectrometer analysis (31). A soluble solids sample was taken of the # apical berries from 25 basal clusters from each plot just before harvest, September 12 and 13. On the day of sampling, the berries were macerated in either a Wiring or Lourdes blender and percent soluble solids of the expressed juice were made with a Zeiss hand refraotcmeter. Approximately 100 grams of macerated berries were saved from each soluble solids sample for nutrient analysis. Due to difficulties in drying, the berries were analyzed on a fresh rather than on a dry weight basis. ’ Soluble solids samples were taken of fruit on September 16 from the top and bottom wire of the trellis at 20 locations. The sample consisted of four apical berries from 25 basal clusters. In 1263, due to a late spring freeze, only #9 of the original 100 plots were used in the survey. Vine vigor was rated numerically from 1 to 5 and the percent of the trellis filled with foliage was visuallyl/ l] “Percent of the trellis filled with foliage" will be referred to as ”foliage density.” 20 estimated. These estimates were made twice during the growing season, July 22 and September 22;/ and averaged for the final.estimate. The vigor rating was found to be more closely correlated.with foliage density (.9h0‘f) than with average shoot growth (.738“). This in- dicated that the vigor rating was a better estimate of foliage density than growth per shoot. Thus, vigor is herein considered to be a measure of foliage density and not of growth. During mid-July, petiole and soil samples were taken and analyzed. A soluble solids sample of 150 berries, 15 per vine, was taken at ran- don.from each plot just before harvest, September 21 and 22. The sam- ples were harvested onto dry ice and held at O°F until fresh weights of the berries were recorded, and percent soluble solids were deter- lined with a Zeiss hand refractometer. All soluble solids samples, in subsequent studies, were processed in this manner. IIIa Nitrogen Study - Growers' Vineyards This experiment was initiated to determine the effect of increased nitrogen on the growth and fruit soluble solids from vineyards of varying degrees of vigor. P e ure: In the spring of 126}, 20 vineyardsgj were selected from the original 100 for this study. The vineyards represented wide ranges in fruit soluble solids, vigor, soil type, and cultural practices. The experimental design was a restricted randomized block with two ;/ The estimate of foliage density on July 22 and September 22 was positively correlated (.907“). This correlation indicates the estimate was repeatable . g/ Due to damage from a late spring freeze, ten of the vineyards were later dropped from the study. 21 replicates per location and 10 vines per replicate. The treatments of no nitrogen and one pound of ammonium nitrate per vine (about four times normal rate), were applied in mid~Apri1 in addition to any fertilizer application made by the grower. The experiment was conducted during 1963 and l96b. Petiole samples, eight per vine, were collected June lh and July 22 in 1963, and June 15 and July 13 in l96h. In the June sam- pling, the first petiole beyond the last cluster was sampled: and in the July sampling, the most recent mature petiole was selected. The samples were analyzed for nitrogen by use of Kjeldahl method. The purpose of the two sampling dates was to determine if plant response was more closely associated.with the petiole nitrogen content in June or July. On July 16, 1963, 10 shoots per plot were marked and weekly growth measurements were made until growth stopped. The weekly growth measurements were plotted and the rate of growth per shoot was calcu- lated from the straight portion of the curve. The date at which shoot extension stopped was recorded for each vineyard. Average shoot growth per vine was obtained by the product of average rate of shoot growth with days of growth. Tbtal shoot growth per vine was determined by the average shoot length per vine times the number of shoots per vine. In 196#, 20 to 25 shoots were measured per plot to obtain average shoot growth per vine. Total shoot growth per vine was calculated as the average shoot growth times average number of shoots per vine. In 1963, leaf area was determined by pressing and tracing the area of 52 leaves onto square centimeter graph paper. The area per leaf was related to the length of the central vein of the leaf as per the 22 equation in Figure 1. From the equation, square meters of leaf area per shoot were estimated by determining and summing the area of all leaves per shoot. Square meters of leaf area per shoot were related to the length of the shoot by the equation in Figure 2. The equation was derived from 36 observations. Each observation was an average of 2 to 5 single observations. Total leaf are per vine was obtained by the average leaf area per shoot times the average number of shoots per vine. The leaf area per pound of fruit was obtained by dividing leaf area per vine by yield per vine. A fruit sample, consisting of 100 berries taken at random per basic plot, was taken September 21, 1963 and September 15, l96h. field and number of clusters per vine were recorded at harvest. weight per cluster was obtained by dividing yield per vine by clusters per vine. Berries per clusterwere calculated by dividing weight per cluster by average berry weight. IV2 Nitrogen Sgugy a Scdus The primary objective of this experiment was to modify vigor by altering the levels of nitrogen available to the vines and to observe the effects on soluble solids. Unlike the nitrogen experiment in growers' vineyards, factors such as soil type, microclimate and cultural practices would be constant. Secondary objectives were to reduce yield, by thinning clusters at two dates during the growing season, to determine the critical period for soluble solids production: to study possible interactions of yield and vigor with soluble solids; and to study the effect of the previous years' 23 Figure l. The relationship of leaf area to the length of the central vein, 1963. LEAF AREA- cm2 500 P l963 . = .99?’ 400 _ [2 = .986 SEE = no.0 so = use: 300 L- 200 P L y=-3.5+ I.Ioe**x2 IOO- ' ‘I/ I l l 1 1 1 4.5 6 9 '2 I5 I8 2| LENGTH OF CENTRAL VElN-cm Figure 20 The relationship of leaf area per shoot to shoot length, 1963. LEAF AREA ISHOOT -m2 L3 r ‘ l963 r =.972** _ r2 {945 see =.osu so =.2ss t y = .0667 + .I36l3**x + .ou722* x2 SHOOT LENGTH - m 25 yield on soluble solids production. Procedure: The experiment was conducted during the summers of 12§2_ and 12§4.at the Sodus Horticultural Farm in Berrien County, Michigan. The design was a factorial split-plot replicated four times with 36 vines per replicate. The basic unit consisted of two vines. The main plots were two levels of ammonium.nitrate, 0 and 1 pound per vine and three levels of sawdust, 0, 23, and 45 pounds per vine. (After drying a sample of sawdust to a constant weight of 150°F, the actual amount applied was found to be 0, 10, and 20 pounds.) The saw- dust was applied in an attempt to reduce available soil nitrogen. (Ten pounds of sawdust per vine based on broadcast application will reduce the availability of nitrogen approximately 45 pounds per acre (41).) In 1963, the sub-plot treatments consisted of (a) no cluster thinning, (b) oneuthird of the clusters per vine removed five days (June 20) after full bloom and (c) one-third removed 50 days (August 5) after full bloom. At the latter date the berries had completed the first stage of growth and the precent soluble solids was 4.0. Petiole samples, 15 per vine, were collected on June 20 and July 27 in 1963, and June 15 and July 15 in 1964. In the June sampling, the first petiole beyond the last cluster was taken; and in the July sampling, the most recent mature petiole was selected. The samples were analyzed for nitrogen. A fruit sample, consisting of 60 berries selected at random per basic plot, was taken September 30, 1963 and September 23, 1964. Yield and number of clusters per vine, berries per cluster and berry weight were obtained in the manner previously indicated. Pounds of prunings removed per vine were obtained in the winter of 1963. RESULTS I, Shading Studies In l962,shading for five weeks preceding harvest or removing the terminal portion of grape shoots to stop linear growth had no significant effect on fruit soluble solids (Table 2). Thinning one-half of the clusters per vine resulted in significant increase in soluble solids only when the vines were not shaded. Removing one-half of the total number of clusters per vine decreased yield by approximately one-half. There was no effect on weight per cluster. The interactions of shade x shoot tip removal and shade x cluster thinning were not significant. In 1963, shading during the early part of the season had no significant effect on soluble solids production, but 50 percent shading for seven weeks preceding harvest reduced soluble solids (Table 3). In 1964, shading to 30 or 50 percent during both periods decreased soluble solids, but the effect was greater during the latter part of the season. The degree or time of shading or the interaction of shade with time had no significant effect on yield, berry weight, or berries per cluster in 1963 or 1964. Exposed shoots produced fruit with higher soluble solids than did shaded shoots on the same vine. There was no significant effect on yield per shoot, berry weight, or berries per clusters (Table 4). II Surve l 62 and 6 In approximately one-half of the 1962 vineyards surveyed, the growers were using a complete fertilizer (200-500 pounds per acre). The fertilizer 26 27 Table 2. - Effect of shading, shoot tip removal and cluster thinning on soluble solids, yield per vine and weight per cluster. Shading studies, 1962. Effect on soluble solids shgge -;% Treatment 0 30 50 Ave. Soluble solids - s Check 15.3 a 15.1 a “ 14.8 a 15.0 a Shoot tips removed 15.3 a 14.9 a 14.6 a 14.9 a Clusters thinned ’ 16.6 b** 15.8 a 15.3 a 15.9 b""'I Average 15.7 15.3 14.9 n.s. Er est 0 eld and wei ht er cluster Treatment Yield - lbsglvine ‘Wt.[c1uste: - l‘bgI Check 14.4 a .22 a Shoot tips removed 14.0 a .21 a 'Clusters thinned 7.8 b** .22 a Shade - 5 0 14.4 a .21 a 30 11.8 a .22 a 50 10.5 a .24 a Shade x shoot tip removal and cluster thinning n.s. n.s. Means followed by the same letter are not significantly different. * Statistically significant at the 5 percent level. ** Statistically significant at the 1 percent level. n.s. not significant 28 Table 3. - Effect of shade and time of shade application on soluble solids, yield per vine, berries per cluster and berry weight. Shading studies, 1963 and 64. Effect on soluble solids -Time of shade; 1263 Time of shade, 1264 17 to 8 7 8 7 to 9 2 19 to 8 7 8 7 to 9 2 Shade - $ Soluble solids - fl 0 14.9 a 15.6 a 16.2 a 16.8 a 30 14.5 a 14.1 a 15.5 b 13.5 b 50 15.6 a 13.5 b** 15.4 b* 13.8 b** Average 15.0 14.4 * 15.7 14.7 n.s. Effect on yieldI berrieschuster and weightlbergy 1963, 1964 Yield - Berries] Wt./berry Yield - Berries] Wt./berry Treatment lbs./vine cluster gms lbs./vine cluster gms Shade - f 0 6.8 a 32 a 3.1 a 10.1 a 25 a 3.1 a 30 7.6 a 35 a 3.0 a 10.2 a 23 a 3.0 a 50 5.6 a 35 a 2.8 a 7.0 a 23 a 2.9 a Time of shade l/ 7 wks. f.b. 7.9 a 29 a 2.8 a 9.0 a 25 a 3.0 a 7 wks. p.h.a/ 5.4 a 38 a 3.1 a 9.2 a 23 a 3.2 a Time x shade n.s. n.s. n.s. n.s. n.s. n.s. y f.b. g] p.h. following bloom preceding harvest 29 Table 4. - Effect of leaf exposure within vines on soluble solids. Shading studies, 1964. Soluble Yield - weight/ Berries/ Shoot solids - % gms/shoot berry - gms cluster Exposed 16.8 202 3.15 24.8 Shaded 15.8 229 2.97 26.1» * n.s. n.s. n.s. grade varied somewhat but was primarily 12-6-24 and 12-12-12. Other growers were using nitrogen singly and in combination with potassium. The nitrOgen was usually applied in the form of ammonium nitrate at the rate of 80 to 200 pounds per acre. Potassium, as muriate of potash, was applied at a rate of 150 to 500 pounds per acre. Some growers were applying manure and lime in addition to the above fertilizer. Trashy cultivation was practiced to some extent in an attempt to reduce vegetative growth and increase fruit soluble solids. Clean cultivated vineyards were often planted to a cover crop of rye in late July or early August. weed control within the row was by cultivation or herbicides. The vines were trained to a fouruarm Kniffin or umbrella system. The Kniffin system predominated. Balance pruning was practiced to some degree by about half of the growers. The number of canes per vine aver- aged about five, but there was a wide variation in number of canes per vine as well as the length of canes. I Yield of the vines and denseness of the foliage varied greatly and low vigor vineyards appeared to be in an alternate bearing cycle. In vineyards with heavy foliage, much of the leaf surface was subjected to shade during a large portion of the growing season. In very high vigor vineyards, leaves in the interior of the vine often turned yellow and dropped before harvest. In 1962, the period from full bloom to harvest was 4 days longer than in 1963. The mean percent soluble solids in 1962 was 16.6 i 1.14 and 15.1» 1’ 1.13 in 1963. Between years, the relative position of the vineyards, with respect to soluble solids, remained fairly constant. This was indicated by the correlation (.605**) of soluble solids in 1962 versus 1963. Petiole potassium was negatively correlated with soluble solids, and other nutrients in the petioles, shoot tips or berries were either inconsistently correlated between years or were not related to soluble solids (Table 5). Soluble solids were positively correlated with soil texture (in- creasing sand content) and percent saturation of the exchange complex with magnesium, and negatively correlated with cation exchange capacity and available calcium. All other soil properties were inconsistently correlated between years or were not related to soluble solids (Table 6). The relationship of soluble solids to magnesium saturation and available calcium was apparently indirect. This was indicated by lack of a correlation of these factors with soluble solids when the effect of cation exchange capacity or soil texture was held constant (Table 7). Soluble solids were correlated with soil texture or cation exchange capacity regardless of any effect due to magnesium saturation or avail- able calcium. Neither cation exchange capacity or soil texture were 31 Table 5.-Re1ati0nship of soluble solids to nutrient content of petioles, shoot tips and grape berries. Survey vineyards, 1962 and 1963. Soluble solids - i 1962 1 6 vs. Petioles Shoot tips Berries Petioles Correlation coefficient Nitrogen -.326“”'l -.110 -.337*‘ n.07l Potassium -.280"”‘' -.041 -=-.228"I -.303* Phosphorus .123 -.022 .056 .050 Calcium -.O67 .181 «.115 -.009 Mbgnesium .272“I .287"I .136 .186 Manganese .088 .016 -.040 .080 Iron .200 .134 -.110 . =.007 Capper -.020 -.043 -.187 2086 Boron -.l30 «.040 c.106 -.105 Zinc -.172 -.043 -~- -.117 Nutrient Mean S.D. Mean S.D. Mean S.D. Mean S.D. N - f .74 .13 2.70 .28 .193 .028 1.09 .16 x - $ 1.47 .60 1.96 .21 .319 .045 2.19 .68 P - 9 .225 .10 .420 .05 .023 .004 .292 .08 c. - 9 1.03 .15 .63 .08 .015 .004 1.06 .17 Mg - s .40 .16 .23 .03 .008 .001 .46 .17 Mn - ppm 396.0 309.0 82.0 52.0 2.7 2.6 265.0 230.0 Fe - ppm 55.0 21.0 104.0 57.0 5.6 1.6 68.0 25.0 Cu - ppm 47.0 51.0 48.0 57.0 2.3 1.6 50.0 61.0 B - ppm 26.0 3.6 24.0 2.8 3.8 .9 31.0 3.9 Zn - ppm 35.0 8.4 31.0 7.9 was man 72.0 22.0 1962, P.05 = .205, P.01 = .267; 1963, P.05 = .288, P.01 = .372 S. D. = Standard deviation (t) 32 Table 6. - Relationship of soluble solids and various soil properties. Survey vineyards, 1962 and 63. Soluble Correlation solids - % gpeffioient 1962 « 1963 73- 1962 1963 Mean S.D. Mean S.D. Soil texture .440** .340* 3.68 1.20 3.98 1.28 pH .248* .084 5.87 .63 6.10 .72 P - 1bs./acre avail. «.168 .366** 105.0 45.0 103.0 50.0 K - lbs./acre avail. -.299*— -.135 192.0 115.0 232.0 177.0 Ca - 1bs./acre avail. -.269* «.296* 950.0 597.0 1010.0 618.0 Mg - lbs./acre avail. c.098 .022 122.0 67.0 117.0 67.0 csc - m.e./100 gms —.43o** s.354* 5.07 2.83 5.89 3.57 K - % saturation .162 .151 5.33 2.94 5.50 4.03 Ca - % saturation .114 .014 49.6 21.7 47.8 23.5 Mg - f saturation .268** .304* 9.7 6.4 9.0 6.7 Percent base saturation .159 .070 63.4 25.9 61.3 28.5 Organic matter - i -.475** .176 2.87 1.28 3.00 1.80 1962, P.05 = .205, P.01 = .267; 1963, P.01 = .288, P.01 = .372 Table 7. - Relationship of soluble solids to various soil propertiesp petiole potassium and vigor. Survey vineyards, 1962. Soluble solids Constant Partial - 5 vs. r effect r Hg - $ saturation .268" CEC “ m.e./100 gms .109 CEC - m.e./100 gms =.QBO** Mg a $ saturation c.364‘* Hg - % saturation .268** Soil texture .086 Soil texture .4#0** Mg a % saturation .371** Ca - lbs./acre avail. ~.269** CEC a m.e./100 gms ~.0h2 CEC - n.s./100 gms -.430** Ca - lbs./acre avail. -.351** Ca - 1bs./acre avail. -=».269""'l Soil texture -.047 Soil texture .hh0** Ca - lbs./acre avail. n.36h** CEC - m.e./100 gms m.430** Soil texture w.l7b Soil texture .1540“l CEC - m.e./lOO gms .200 Petiole K - i m.280** Vigor m.l76 Vigor ~.52#** Petiole K u f :==i.l+87""'l P.01 = .267 Partial r or partial correlation coefficient measures the correlao tion between the dependent factor (soluble solids) and each of the several independent factors (cation exchange capacity. soil texture, etc.,) while eliminating any tendency of the remaining independent factor (5) to obscure the relation. For example, there was a significant positive correlation (r) between soluble solids and soil magnesium. However. when either cation exchan e capacity or soil texture were taken into consideration (constant effect , there was no significant correlation between soluble solids and soil magnesium. correlated with soluble solids if the effect of ene or the other was held constant. This indicates that the effect of the soil is reflected to the same extent by either soil texture or cation exchange capacity. The apparent relation of soluble solids to petiole potassium was in» direct as indicated by the lack of a correlatien ef soluble solids and pet- iole potassium when the effect of vigor was held constant (Table 7). Vigor, as determined by a vigor ratingo was inversely related to 3g soluble solids (Table 8). The 1963 foliage density and 1962 yield. as indicated by number of clusters per vine. were negatively correlated with soluble solids. Soluble solids did not vary consistently with spacing within or between the row nor with trellis height. but were consistently correlated with square and cubic feet per vine. When the effect of vigor was held constant. square feet per vine was not corre= lated with soluble solids. Soluble solids were not related to row direction, position of the shoots on the trellis or soil management. Thus. in summary. the factors associated with variation of solum ble solids were cation exchange capacity and/or soil texture. square feet of soil surface per vine. vigor and/or foliage density and clusters per vine. The relation of these factors to soluble solids is shown in Figures 3 - 7. The relation of cation exchange capacity (Figure 3) and soil texture_(Figure 4) to soluble solids was slightly greater in 1962 than in 1963. The relation of square feet of soil surface per vine was slightly greater in 1963 than in 1962 (Figure 5). III. NitroEen Study m Growers” Vineyards Application of one pound of added ammonium nitrate per vine sub» stantially increased petiole nitrogen compared to vines receiving none (Table 9). Vines receiving the additional nitrogen in 1963 had eight percent higher petiole nitrogen in June than the check vines and 13 per» cent more in July. The reverse occurred in 196“ with an 18 percent inn crease in June and a 13 percent increase in July. The nitrogen applica» tion had no effect on yield per vine. clusters per vine. berries per cluster, leaf area per pound of fruit. shoot growth. foliage density or soluble solids in 1963 or 1968. The interaction of applied nitrogen 35 Table 8.-Relationship of soluble solids to vigor, foliage density. clusters per vine and cultural practices. yards, 1962 and 63. Survey vine: Soluble solids 1962 l963 - f vs. r Mean S.D. r Mean S.D. Vigor rating ~.524** 3.36 .88 c-.733"”‘I 3.26 .94 Foliage density - i ,--- ,--- ,--- c.803‘* 57.1 23.0 Clusters/vine =.u25** 9a.0 25.0 .--- -a- --- Spacing within - ft. .117 8.9 1.2 .300* 8.9 1.1 between - ft. .233** 9.2 .78 .05fi 9.4 .69 Trellis hei ht - ft. .Oh6 b.72 .35 v.18? “.67 .35 Square feet vine .2“?* 82.0 12.0 .308* 83.0 12.0 Cubic feet/vine .237* 387.0 66.0 .289’ 386.0 65.0 Square feet/vine + constant foliage .183 .cea .aaa .136 can an: density effect Factor Row direction Soluble solids a 5 north 16.7 n south 16.2 °S° Position top wire 16.9 bottom wire 16.6 n°5° Soil management clean cultivation . trashy cultivation 15.9 n.s. 1962, P.05 = .205, P.05 = .267; 1963. P.05 = .288, P.01 = .372 36 Figure 3. The relationship of soluble solids to cation exchange capacity. Survey vineyards, 1962 and 63. l9- I8- SOLUBLE souos- °/. '5; :3 I 6': |962 |963 r =-1430** "3352* SEE = |.O3 '-07 so : I.I4 '-l 3 I73**X I—SS=I6.I-.lll*x |963 I I | I 4 I2 I3 I l l ' l l I 2 s 4 5 e 7 e 9 IO II canon EXCHANGE CAPACITY- m'e/IOOQ 3? Figure 4. The relationship of soluble solids to soil texture. Survey vineyards, 1962 and 63. |7~ I6- SOLUBLE SOLIDS - °/o CLAY LOAM- LOAM |962 l963 .440** .340* q M II II II 493 .II6 see L03 L07 so =IJ4 LIS I962 SS=I4.7¢ .4l7”X I963 Lss-n4.3+.zee*x l I J 3 4 5 SANDY LOAM LOAMY SAND-SAND SAND SOIL TEXTURE 3'8 Figure 5. The relationship of soluble solids to square feet of soil surface per vine. Survey vineyards, 1962 and 63. SOLUBLE SOLIDS - °lo I91- I962 I 963 r = 247* 309* r2 = .06| .095 I8 _ sea =|J| LOB so = I.|4 us [7 .. ' I962 [SS = l4.3 + .0234*X I6 - \ss =13.0+ 0294* x l5 - - I4 - I35: lfil l l l I l J 60 7O 80 90 IOO IIO IZO SQUARE FEET IVINE 39 Figure 6. The relationship of soluble solids to number of clusters per vino. Survey vineyards, 1962. S OLUBLE SOLIDS - °lo l9 - l8 . r =-.425** :2 = .IBI see = n.04 so = I.I4 l7 - '3 .. rSS=I8.0-.Ol9**x l5 - |963 l4 - l3.5- ’ ,v ‘9}! l l I l l J 40 60 80 mo l20 I40 l60 NUMBER OF CLUSTERS/VINE Figure 7. The relationship of soluble solids to folisge density. Smey vineysnds, 1963. SOLUBLE SOLIDS -°/o '7 r. r =—.803** r2 = .645 SEE = .68 so = l.|3 I6 - / $8 = I7.7- .0389**X I5 - ' I4 - I963 I3 - l2.5 Ab L41 I l I l 4 I 20 4O 60 80 I00 FOLIAGE DENSITY - °/e #1 Table 9. - Effect of nitrogen application on petiole nitrogen, yield per vine, clusters per vine, berries per cluster, weight per berry, leaf area per pound of fruit, shoot length, fo- liage density and soluble solids of Concord grapes. Nitro- gen stndy - grovers' vineyards, 1963 and 61+. Factor Check N Check N Petiole n - $ dry at. June 1.56 1.69" 1.26 1.50" July 1.08 1.24" 1.17 1.35" Yield - lbs. Ivine 16.1 15.0 19.3 19.3 Clusters/vine 80.0 76.0 11.1.0 no.0 Berries/cluster 29.7 29.0 26.6 25.2 Ute/berry - w 2e99 3e02 2.9+ 2e97 Leaf area/lb. of fruit 4. 1.12 1.15 .91 .9!» Shoot length - n 2.05 2.13 1.73 1.73 Foliage density - i 55.0 58.0 53.5 62.11 Soluble solids - 15 15.7 15.7 16.3 16.2 with locations was sipificant for berry weight in 1%“. All other interactions were not significant in 1963 and 196‘}. The petiole nitrogen content, from the check plots, was positively correlated with growth and leaf area per shoot regardless of the time or the year the petioles were sampled. Growth and leaf area, per sheet were "lore highly correlated, in 1963 with the nitrogen content of petioles col- lected in June than in July. The correlations did not differ with date of sampling in 190+. Soluble solids were not correlated with petiole “111mg“ at any smiling date or year (Table 10). Since there was no effect of applied nitrogen on any of the factors “med except petiole nitrogen and berry weight, the din for nitrogen trea.‘l‘ments were pooled for both years. The pooled data were subjected to I42 correlation and regression analysis- (24) in order to study the rela- tionship of soluble solids to foliage density, growth and yield. There were 20 observations per comparison. Table 10. - Relationship of growth and leaf area per sheet and soluble solids to petiole nitrogen. Nitrogen study - growers' vineyards, 1963 and 61+. Petiole n - 5 . o d vs. 3710/63 77222’2'3 :12! L' ';%7“15%—'7'7 13" 761E Correlation coefficient Growth/shoot .. n 2 .618" .088- .681" ‘ .687" Leaf area/shoot - n .551" A53“ .705“I .670“ Soluble solids - f -.231 -.199 -.076 -.293 P.05 I .W, P.01 II .561 Soluble solids were negatively correlated in 1963 as indicated by simple correlations with foliage density, shoot growth per vine, shoots and yield per vine. They were not correlated with rate or days or growth. Soluble solids were correlated with foliage density only in 1961} (Table 11). The negative correlation of soluble solids to ”shoot Growth per vine in 1962 was indirect and apparently due to the influence 01‘ shoot growth on foliage density. This was indicated by the lack of a °°rrelation of soluble solids with shoot growth per vine when the effect 01‘ foliage density was held constant. Soluble solids were found to be P°81tively correlated with days of growth when the masking effect of 1‘ c’31—:l.age density was removed. As indicated by simple and/or partial corre- htion, soluble solids were negatively related to yield in 1963 but not in 43 Table 11. - Relationship of soluble solids to foliage density, growth, yield per vine and leaf area per pound of fruit. Nitrogen study - growers! vineyards, 1963 and 61+. 964 Constant Constant Soluble solids foliage, foliage, - f vs. Simple r Partial r Simple r Partial r Foliage density - i «870“ «600" Shoot growth/vine - n «687" .260 -.10u .110 Shoots/vine -.7u9" «580" .081 -.079 Growth/shoot - n -.u29 .3b6 -.178 -.271 Sheet growth/wk. - on «395 .329 -- .... hys of shoot growth .05# .622Ml -- --- field - ,lbs./vine «711" -.60#“ -.392 «#53 loaf-grea/lb. of fruit -.107 $91" .215 .486" simple r, P.05 :- .m, 9.01 a .561; Partial r, P.” 2 A56. P.01 - .575 1964. leaf area per pound of fruit was not correlated with soluble solids in ‘either year as indicated by simple correlation. However, there was a P081tive correlation with soluble solids in both years when the asking °ffoct of foliage density was removed. The relationship, of foliage density to leaf area per sheet and nun- 1hr of sheets per vine in 1962 and 1963 is shown in Table 12. Foliage duality increased in 1963 with increasing leaf area per shoot and number of shoots per vine. These two factors were associated to about the sane uh Table 12. - Relationship of foliage density to leaf area per shoot and shoots per vine. Nitrogen study - growers' vineyards, 1963 and 64. __l2é2__ Foliage density (f) I -2u,6 + 73.0"}{1 + 1.52eax2 where x X1 I leaf area/shoot - 1:2 X2 I shoots/vine R I .3“): Beta “.1 I .5” S.E.E. 8 13.6 R?- .713 Beta “.2 - .563 3.0. =- 211.0 _12.6_4___ Foliage density (fi) I 17.8 + lh6.2**X.1 - .25X2 where: X1 8 leaf area/ shoot - :12 X2 I shoots/vine B I .669 Beta wt.1 - .641 S.E.E. '- 15.3 32- .M? Beta wt.2 - .12» S.D. - 19.5 R - Multiple correlation 32‘ Coefficient of multiple determination and represents the proportion of the total variation in the dependent factor (foliage density) Vhich can be explained by, or is associated with, variation in the independent factor or factors (leaf area per shoot and shoots per vine). 3°“ wt. 8 Beta weight and neasm-es the relative importance of each of the independent factors in explaining or predicting variation in the dependent factor. .S' E.E, . Standard error of the estimate and measures the closeness with which the estimated values of foliage density agree with the actual values of foliage density. S'D- = Standard deviation of foliage density. 45 degree with foliage density. This is indicated by the beta. weights which were essentially equal. The 32 value multiplied by 100 indicates that leaf area per sheet and number of sheets per vine accounted for about 71 percent of the total variation in foliage density. Only leaf area per shoot was significantly related to foliage densityin 1964 and accounted for about 45 percent of the total variation. The effect of leaf area per sheet in foliage density was greater in 199+ than 1963. This is indicated by the difference in the beta weight for leaf area per shoot between the two years. The two factors directly associated with variation of soluble solids were leaf area per pound of fruit and foliage density (Figure 8). Variation of foliage density and leaf. area per pound of fruit accounted ' for 81.5 percent of the total variation in soluble solids in 1963 and 149.1 percent in 1961*. These percentages were obtained by multiplying the 32 values by 100. Although the percentage of the total variation in soluble solids that could be explained on the basis of these two factors varied between years, the total association of soluble solids to foliage density and leaf area per pound of fruit was the same in both years. This is shown by the lack of a difference in the standard Orr-or of the estimate for the two years. The standard error of the Oatimate in 1963 was .60 as compared to .52 in 196+. However, the ClGent-es to which soluble solids were associated with each factor varied between years. Variation in foliage density in 1963 had a greater effect on 8"liable solids than did variation of leaf area per pound of fruit (Figure 8). This is indicated by the beta weights. The beta weight f °1‘ foliage density was about three and one-half times greater than that Figure 8. lt6 The relationship of soluble solids to leaf area per pound of fruit and foliage density. Nitrogen study - growers' vineyards, 1963 and 64. ‘ The figures were constructed according to the following equations: 1263 Soluble solids = 18.20 + ,5756‘X1 ' .0531**X2 l2é’i—_ Soluble solids = 16.86 + .8606*x1 - .0235*‘X§ Z; '63 :3 3 I SOLUBLE SOLIDS - °/o I I963. R = .903“ R2 = 8:5 Beta wt. = .262 - Beta wt2=-.969 SEE = .60 SD =l.3l I.O LS 2.0 22 LEAF AREA no. FRUIT- m2(x ,) SOLUBLE SOLIDS - °lc 13 '5 I I 0 0| l4 |964 R = .70|** R2 = .49: Beta wtl = .366 Beta M2 =-.648 SEE .52 SD .7I .4 .5 Lo I.5 LB LEAF AREA /lb. FRUIT-mam.) 41' for leaf area per pound of fruit. The effect of foliage density on soluble solids in 1964 was greater than the effect of leaf area per pound of fruit. This is shown by the difference in the beta weights. . A comparison of the portion of the plane due to foliage density in 1 each year shows that this factor had less effect in 1961; than 1963. This further supported by the difference in beta weight for foliage density. The beta weight for foliage density was -.969 in 1963 as compared to -.648 in 196“. Leaf area per pound of fruit had slightly more“§ffect on soluble solids in 1968 than 1963. In either year, the highest soluble solids were associated with low foliage density and high leaf area per pound of fruit: whereas, the lowest soluble solids were associated with high foliage density and low leaf area. An increasing leaf area per pound of fruit was associated with an in- crease in soluble solids only if the foliage density remained fairly constant. Mean soluble solids were slightly higher in 196% than in 1963, and soluble solids variability in 196“ was about one-half that of 1963. Mean foliage density did not differ between years. leaf area per pound of fruit and leaf area per shoot were higher in 1963 than in 196#: whereas, yield per vine and number of shoots per vine were less. The variation of all these factors, except sheets per vine, was greater in 1963 than in 1964 (Table 13). - Climatic and phonological data for 1963 and 196” are shown in Thble It. The number of heat units accumulated above 50°F before flull bloom.was essentially the same in 1963 and 196k. Dmys from.full bloom to harvest was 101 in 1963 and 99 in 196“. Heat units accumulated during the first 30 days, second 30 days and residual days were greater 48 Thble 13. - Variation of soluble solids, foliage density, leaf area per pound of fruit and per sheet, yield per vine, number of shoots, rate of shoot growth and days of growth. Ni- tmgm study - growers' vineyards, 1963 and 64. __1963 ___1§64 Factor Mean c.v. - 9 Mean c.v. - $ Soluble solids - i 15.7 8.3 16.2 4.4 Foliage density - f 59.2 40.5 58.0 33.8 leaf area/1b. of fruit - m2 1.14 52.6 .91 33.0 Leaf area/shoot - m2 .44 47.7 .37 27.0 rield - lbs./vine 15.5 43.2 19.3 29.0 Shoots/vine 36.1 23.0 47.2 23.0 Shoot growth/wk. - cm 16.4 52.4 --- --- hys of shoot growth 64.1 15.0 --- --- C.V. = coefficient of variation for each period in 1964 than in 1963. The difference in heat units was greater during the first two periods. Average soluble solids, adjusted for differences in leaf area per pound of fruit and days from full bloom to harvest, were greater in 196+ than in 1963. Total rainfall during the period from full bloom to harvest was greater in 1963 than in 196+. The rainfall in 1963 was less during the first 30 days, and greater in the second 30 days and the remaining days before harvest than in 196+. 49 Table 14. - Phonological and climatic variation. Nitrogen study - growers' vineyards, 1963 and 64. Phonological variation (a) (b) l/ Bloom Harvest rays - Soluble Year date date (a to b) solids - i 1963 6/13 9/21 101 15.3 1964 6/9 9/15 99 16.6 Climatic variation Heat units - degree daysg/(bloom to harvest) Heat units lst 30 2nd 30 Residual Year to bloom days days days Tbtal 1963 616 524 667 575 1772 1964 621 718 738 582 2036 Rainfall}! 1963 .60 5.38 1.91 7.89 1964 2.75 .67 .83 4.25 1/ Adjusted for differences in leaf area per pound of fruit by equations in Figure 8. Adjusted for differences in days from full bloom to harvest by adding .2 percent units per day difference. Obtained by accumulating daily average and minimum temperatures minus 50°F base temperature (Pew Paw Station). '2 2f Paw Paw Station 1V. Nitrogen Study - Sodus Application of one pound of ammonium nitrate per vine increased petiole nitrOgen compared to vines receiving no additional nitrogen. The increase was evident at both sampling dates in 1963 but only for the June sampling in 1964 (Table 15). Vines receiving the additional nitrogen in 50 Table l5.- Effect of nitrogen application on petiole nitrogen, yield per vine, clusters per vine, berries per cluster, weight per berry, number of buds, pruning weight, foliage density 22d fruit soluble solids. Nitrogen study - Sodus, 1963 and 1 631, 1264 Factor eck N Check Petiole n - 9 dry wt. June 1.09 1.25" 1.24 1.61" July .90 1.06" 1.27 1.32 Yield - lbs./vine 18.3 16.7 20.4 21.6 Clusters/vine 143.0 132.0 106.0 114.0 Berries/cluster 37.4 37.9 27.3 26.4 Wt./berry - gms 3.18 3.14 3.24 3.24 Pruning wt. - 1bs./vine 3.5 4.3" --- --- Buds/vine 48.9 47.1 53.6 62.7* Foliage density - $ --- --- 54.0 64.0* Soluble solids - $ 16.6 16.5 16.4 16.0* Table l6.-»Effect of thinning clusters on petiole nitrogen, yield per vine, clusters per vine, berries per cluster, weight per berry, pruning weight, buds per vine, and fruit soluble solids. Nitrogen study - Sodus, 1963. Clusters thinned Factor Check 6/29763 8/5/63 Petiole N - 9 dry wt. June 1.19 1.16 1.16 July 099 098 097 Yield - 1bs./vine 21.4 a 17.3 b 13.7 c" Clusters/vine 186.0 a 112.0 b 115.0 b** Berries/cluster 33.1 a 43.6 b 36.6 a“I Wt./berry - gms 3.12 a 3.28 b 3.07 a"“‘I Pruning wt. - 1bs./vine 3.7 4.1 3.7 Buds/vine 45.7 51.8 46.5 Soluble solids - 9 15.9 a 16.7 b 17.0 b" 51 1963 had 13 percent higher petiole nitrogen in June than the check vines and 15 percent higher in July. There was a 23 percent petiole nitrogen increase in June 1964. The nitrogen application had no effect on yield, clusters per vine, berries per clusters, or berry weight in 1963 or 1964. The nitrogen application in 1963 resulted in an increase in pruned weight, but this was not associated with a change in soluble solids. The greater pruned weight in 1963 due to the nitrogen application resulted in a larger number of buds per vine after pruning in the spring of 1964. This larger number of buds was associated with greater foliage density and lower fruit soluble solids in 1964. Application of sawdust and the interaction of sawdust and nitrogen did not have a significant effect on any of the factors studied. Removing one-third of the total number of clusters per vine on either 6/20/63 and 8/5/63 reduced yield, but the difference was greatest when the clusters were thinned early. Thinning early resulted in an in- crease in the number of berries per cluster and weight per berry. Thin- ning at both dates increased soluble solids, but the magnitude of in- crease did not vary with date of thinning (Table 16). There was no significant effect of the 1963 cluster thinning on any of the factors studied in 1964. The interaction of cluster thinning at either date with nitrogen or sawdust application was not significant for any factor studied. DISCUSSION Effect of Shading and Foliage Density on Soluble Solids Increasing the leaf to fruit ratio by thinning clusters resulted in an increase in soluble solids only if the vines were not shaded. Also, an increase in leaf area per pound of fruit was associated with an increase in soluble solids only if the foliage density remained rela- tively constant. This indicates that the effectiveness of the leaf to fruit ratio is dependent on exposure to sunlight, and that increasing the leaf to fruit ratio does not necessarily result in an increase in soluble solids. This occurred in the vine and shoot shading experiments and in a similar shoot shading study by Shaulis (52). Sites and Reits (56) found that fruit soluble solids of Valencia oranges were highest when the fruit was borne on the top portion of the tree; lowest when borne inside the tree and intermediate when borne at other positions. The depressing effect of increasing foliage density may be explained on the basis of a reduction in light intensity, due to mutual shading of the leaves, resulting in lower photosynthetic efficiency per unit leaf area. Such an effect of foliage density on fruit soluble solids of the Concord grape has also been suggested by Kimball and Shaulis (33). As has been pointed out by Heinicke and Childers (28) and Kramer and Clark (34), maximum photosynthetic rates, under usual atmospheric carbon dioxide concentrations, are attained at a light intensity of one-fourth to one-third full sunlight. However, as has been pointed out by Meyer and Anderson (40), such results are obtained only when a single leaf or a small plant, in which there is little or no shading of one part by another, is used as the experimental material. When the effect of light on photosynthesis is considered in terms of an entire tree, a 52 53 different relationship holds. Heinicke and Childers (28) have shown that the rate of photosynthesis for an entire apple tree increases in preportion to increased light intensity up to or nearly that of full sunlight. In Michigan vineyards, the case of the single leaf or small plant is approached in vineyards of low foliage density; and the case of the dense foliage plant, or apple tree, is characteristic of vine- yards with high foliage density. Further evidence that the effect of foliage density on soluble solids production is due to inadequate exposure of the foliage to sun- light was obtained by altering the conventional trellis. The alteration was made in a southwestern Michigan vineyard by the grower. The conyen- tional four-arm Kniffin training system (37) was altered to a modified Hunson system. The Munson training system (55) was modified in that the central wire was omitted, leaving two wires that passed over the ends of 2 x 4 wood cross-pieces about 21 inches long, set at right angles to the row on posts five feet high. This trellis provided better exposure of the foliage to sunlight. During the 1964 harvest season, fruit yields, berry size and fruit soluble solids were obtained from 17 three vine plots of the modified trellis and compared to a like number of observa- tions from adjacent Kniffin trellised vines. Vines trained on the modified Munson trellis produced fruit with higher soluble solids than vines trained on the four-arm_Kniffin trellis (Table 17). Soluble solids were consistently higher in all 17 three vine plots. There were no differences in yield or weight per berry. In this comparison of training systems, the foliage density of the check plots averaged 65.5 percent. Thus, considering the relationship of soluble solids and foliage density, the effect of such a change in 54 Table 17. Effect of trellising on soluble solids, yield per vine, and weight per berry, 1964. Soluble Yield weight Training solids - $ lbs./vine berry - gms Khiffin 14.8 21.0 3.18 Nbdified anson 15.? 21.0 3.25 ‘* n.s. n.s. training on soluble solids would be expected to become greater with in- creasing foliage density. In the shading studies, the effect of foliage density on soluble solids appeared to be expressed during the few weeks before harvest. This is in agreement with published information that the rate of soluble solids accumulation increases during the few weeks before harvest (18). The depressing effect of increased density on soluble solids does not appear to be due to growth pg; gg. This is evidenced by the lack of a correlation of soluble solids with growth per shoot or rate of growth. Also, soluble solids were positively correlated with days of growth. If the depressing effect of denser foliage on soluble solids was due to growth pg;,§g, a negative correlation would be expected with days of growth. In addition, removing the terminal portion of the shoot tips did not influence soluble solids, but terminal growth may have ceased when the treatment was applied (August 15). In 1963, the average date on which shoot extension ceased was August 15 3 9.6 days. The correlation of square feet per vine with soluble solids was an indirect relationship of foliage density and vine spacing. There was no 55 correlation of soluble solids with square feet per vine if the effect of foliage was held constant. Such an effect of spacing on soluble solids has been demonstrated by Kimball and Shaulis (34). They found that removing part of the vines in a vineyard of high foliage density and thus increasing spacing resulted in an increase in soluble solids. They attributed this increase in soluble solids to better exposure of the foliage to sunlight. Variations in trellis height appeared to have no influence on soluble solids. However, the effect of trellis height and spacing on soluble solids cannot be adequately evaluated in a vineyard survey. This is due to the lack of a consistent relationship between vigor and spacing. For example, a vineyard with wide spacing may have high vigor vines while another vineyard with the same spacing may have low vigor vines. Thus, in this study, no definite conclusion could be made con- cerning the effect of trellis height or spacing on soluble solids. Considering the effect of shading on soluble solids production, grapes grown on the top wire of the trellis would be expected to have a higher soluble solids content. Such was not the case (Table 8). This was probably due to the higher yields which are usually produced on the top wires (37). Also, a larger number of canes may have been left on the top wires, resulting in denser foliage on the top wire than on the bottom. Effect of Variation of leaf Area per Pound of Fruit on Soluble Solids The increase in soluble solids, obtained by thinning clusters was probably due to increasing the leaf area per unit of fruit. The effect of the leaf to fruit ratio appeared to be expressed primarily during the 56 the ripening period as indicated by the cluster thinning experiment at Sodus. The increase in soluble solids, obtained by removing clusters following full bloom, was not different from the increase obtained by removing clusters immediately before the ripening period began. Effect of Nitrogen on Fruit Soluble Solids Applying one pound of ammonium nitrate per vine, at Sodus, did not affect soluble solids, but increased growth as measured by pruned weight. Since these vines were balance pruned (37), a larger number of buds were left in 1964 on vines receiving nitrogen. This increase in bud number was associated with an increase in foliage density and lower soluble solids in 1964. The effect of nitrogen indirectly re- sulted in an increase in foliage density. In the survey plots, which were not balance pruned, applications of nitrogen had no effect on shoot length or soluble solids. Petiole nitrogen.was positively correlated with shoot length and leaf area per shoot. This appears to be somewhat contradictory, but was probably due to the wide range in nitrogen content in the soil between vineyards as compared to the small increase obtained by nitrogen application. In 1963, 50 percent of the total variation was due to nitrogen content between vineyards while only 15 percent was due to the current season's nitrogen application. In 1964, these percentages were 56 and 18, re- spectively. The difference obtained in petiole nitrogen, due to ap- plication of nitrogen, may not have been of sufficient magnitude to affect shoot length, shoot weight and/or soluble solids. If there was an effect it may have been masked by differences in pruning severities. 57 Continuous applications of high levels of nitrogen, over a period of years, would be expected to affect soluble solids production as shown by the results at Sodus and by the positive correlation of growth and petiole nitrogen. Higher than normal applications of nitrogen would be expected to increase foliage.density and yields and decrease soluble solids. But if the trellis could be modified to provide adequate fo- liage exposure, nitrogen application would be expected to increase yields and soluble solids until no further increase in the leaf area per unit of fruit was obtained. NitrOgen pg;,§ggwould not be expected to decrease soluble solids production by inducing excessive growth (Figure 2). The quadratic equa- tion of leaf area per shoot to length of shoot indicates that as length of shoot is increased there is a more rapid increase in leaf area; and thus potential net carbohydrate production per shoot increases at an in- creasing rate. It may be suggested that net carbohydrate production does not in- crease on high vigor shoots since a large portion of the leaves may be immature and thus dependent on the older leaves on the same shoot for carbohydrates. This does not appear to be the case. Data of Hale and weaver (25) indicate the number of immature (nonuexpanding) leaves of vinifera grapes averaged about 7.4 and remained relatively constant with time. In 1964, a similar situation was found to exist with the Concord variety. The number of immature leaves remained relatively con- stant and averaged 8.9. Also, Hale and weaver (25) found that the grape leaf started transporting assimilates when half its final size. Since the number of immature leaves remains relatively constant, the ratio of mature to immature leaves per shoot would be expected to 58 increase with time. This is confirmed by calculations from the data of Halo and Weaver (25). Thus, carbohydrates production per shoot would be expected to in- crease~with increasing shoot length and leaf area.per shoot. This is suggested by the positive correlation of soluble solids with leaf area per pound of fruit and days of growth. The relationship of soluble solids to days of growth (Table 11) was probably due, in.part, to the positive correlation (.744**) of days of growth and leaf area per shoot. Effect of Soil Texture andlor Cation Exchange Capacity,on Fruit Soluble Solids The positive correlation of soluble solids with soil.texture and negative correlation with cation exchange.capacity was low but consistent between years. The effect of these soil factors on soluble solids is probably due to an indirect effect on foliage density and possibly leaf area per unit of fruit. The low degree of correlation of soluble solids with soil texture and cation exchange capacity may be due, in part, to the method of soil.sampling. The soil.samples were taken to a depth of about six to eight inches. Such a.sampling procedure does not provide conclusive information concerning the nature of the soil in the root zone. Variation of Fruit Soluble Solids Between Years The leaf area per pound of fruit was less in 1964 than in 1963. This was reflected by a slightly greater effect of leaf area per pound of fruit.on soluble solids in 1964 than in 1963. The higher leaf area per pound of fruit in 1963 was due, in part, to the lower yield and 59 greater leaf area per shoot in 1963 than 1964. The effect of foliage density was less in 1964 than in 1963. This difference in foliage density may have been due to the difference in climatic conditions. In 196#, the total number of heat units accum- ulated was greater than in 1963. Most of the difference in heat units occurred during the first 60 days after full bloom. This early heat unit accumulation probably resulted in an earlier development of the maximum leaf area per shoot in l96h than in 1963. Clore and Bryant (16) have also suggested that high heat accumulation early in the sea- son results in earlier develOpment of shoot growth of the Concord grape and high soluble solids. Winkler (68) has shown that the time of ma- turity of grapes is positively correlated with time to development of maximum leaf area. Thus, an increase in the time of maximum leaf area in 1964 compared to 1963 would be expected to result in higher soluble solids in 1964 than 1963, as was the case. The correlation of foliage density in 1963 with that in 1964 was .916". Thus, foliage density remained fairly constant between years. Leaf area per shoot was positively correlated with foliage density in both years. Thus, the effect of an early development of maximum leaf area on soluble solids would be expected to increase with increasing foliage density. Vineyards which produced relatively low soluble solids in 1963, due to denser foliage, produced relatively higher soluble sol- ids in 196# at the same level of foliage density. This would help to explain part of the reduction of soluble solids variation in 196# as compared.to 1963 (Table 18). The reduced effect of foliage density on soluble solids in 196# was perhaps also due to higher light intensityo The effect of foliage 60 Table 18. - Seasonal variation of soluble solids according to foliage density. Foliage Soluble solids - density - fl 1§Z3 lgéé Difference 75 g 100 lh.l 15.8 1.7 50 - 7“ 15.0 16.“ l.b below 50 l6e9 l6e8 " e1 1] Data were adjusted for yield by equation in Figure 8. density would be less with an increase in light intensity. The soluble solids change between years would be expected to increase with an increase in foliage density. An increase in light intensity would result in a re- duced variation of soluble solids in 1964 as compared to 1963. The distribution and amount of rainfall may have affected the variation of soluble solids between years. Rainfall during the first 30 days after full bloom was greater in 1964 than in 1963. This may have resulted in an earlier development of maximum leaf area in 1964. The rainfall following the first 30 days after full bloom and to harvest was greater in 1963 than in 1964. This may have been associated with more cloudy days and lower light intensity in 1963 than l96h. Therefore, it appears that soluble solids may be positively corre- lated with days of growth within any particular year provided the foliage exposure is adequate. This would be expected since leaf area per unit of fruit is limiting soluble solids production. However, between years, soluble solids would be expected to be negatively correlated with days of 61 growth provided the leaf area per unit of fruit does not vary dras- tically between years. The early development of the maximal leaf area would result in a longer period of photosynthetic activity. The fact that some vineyards are consistently low or high with respect to soluble solids can probably be explained on the basis of the constancy of the foliage density. The variation of average soluble solids from year to year is probably a response to difference in temperature and/or light intensity between years. Also, the amount and time of rainfall and associated cloudy weather may be important. In each year of this study (1962 - 196“), average soluble solids was relatively high. During years of more unfavorable conditions for soluble solids production, the effects of spacing, soil type, leaf area per unit of fruit and foliage density would be expected to be accentuated. Obviously, the growers have little control over climatic varia- tion between years. But they should be able to change growing condi- tions or cultural practices to increase soluble solids within any particular year as well as reduce variation between years. In these studies, the major vineyard and cultural factors influencing soluble solids were those associated with foliage shading and to a lesser ex- tent with leaf area per unit of fruit. As shown in Table 19, fruit soluble solids were lowest with the highest levels of foliage density, fruit yields, soil cation exchange capacity and/or soil texture and close spacing. In order to achieve maximum fruit soluble solids, the grower should (1) modify the trellis to insure maximum leaf exposure to sun- light, and (2) initiate practices to increase the leaf to fruit ratio. 62 Also, planting vineyards on soils of medium or low cation exchange capacity with adequate spacing would be expected to result in slightly higher soluble solids, but would probably reduce yields. waever, since both the effect of soil and spacing on soluble solids appear to be indirect, these effects might be eliminated if the trellis was modified to provide exposure to sunlight. 63 Table l9.-Relationship of soluble solids to foliage density, clusters per vine, cation exchange capacity, soil texture and square feet of spacing per vine. Survey vineyards, 1962 and 63. 3:11:31 . 1:51;. “3:3?“ c.5053?) .3211. $735. 1962 15.0 or less ‘15)lJ’3.7 110 7.8 2.8 77 15.1 - 16.0 (27) 3.9 102 5.7 3.2 82 16.1 - 17.0 (33) 3.2 83 3.9 u.3 82 17.1 or above (16) 2.5 83 3.1 4.3 88 33:35“. . 5:13:51 a ”$05 21:" .3113... .3373; 1963 15.0 or less (15) 83 6.6 3.7 9h 15.1 - 16.0 (16) 50 6.8 3.7 92 16.1 - 17.0 (15) uz ' u.6 u.3 88 17.1 or above (2) 33 3.0 5.0 97 1] Number of vineyards in soluble solids class. SUMMARY An investigation was initiated to determine factors associated with variation of fruit soluble.solids of Concord grapes in.Eflchigan. The investigation involved (I) shading, shoot tipping and cluster thinning experiments, (2) a vineyard survey and (3) nitrogen studies. Soluble solids were increased by cluster thinning (increasing the leaf to fruit ratio) only when the vines were exposed to full sunlight. Shoot tipping had no effect on soluble solids, regardless of degree of shade (sunlight). The survey revealed that shading, due to high foliage density, and a low leaf to fruit ratio was a problem in many vineyards. A more detailed study indicated that foliage density and leaf area per unit of fruit accounted for a high percentage of the total variation of fruit soluble solids. The effect of foliage density was greater than the effect of leaf area per pound of fruit. Growth per shoot, rate of shoot growth, or days of growth were not inversely related to soluble solids. modifying the trellis to provide better exposure of the leaf surface to sunlight resulted in greater produc- tion of soluble solids. Applications of nitrogen had no effect on soluble solids, yield per vine or growth in the growers'vineyards. Ibwever, at Sodus, ap- plication of nitrogen increased growth when measured as pruned weight. This resulted in more buds per vine in 196“ with greater foliage density and lower soluble solids. The difference in growth response to nitrogen between the growers' vineyards and the Sodus vineyard was probably due to balance-pruned vines and less soil variation at Sodus. 6h 65 To increase production of soluble solids, the grower should initiate practices to provide better leaf exposure and increase the leaf area per unit of fruit. 2. 9. 10. 12. REFERENCES CITED Alderfer, R. B., and H. K. Fleming. 1948. Soil factors in- fluencing grape production on well drained lake Terrace areas. Penn. Agr. Exp Sta Bul. #95: 2h pp. Alwood, Williams B., B. G. Hartmann, J. R. Eoff, S. F. Sherwood, J. 0. Carrero, and T. S. Harding. 1916. The chemical com- position cf American grapes grown in the central and eastern states. 0. 5. Dept. Agr. Bul. l$52: 20 pp. Amerine, M. A., and A. J. Winkler. 1963. California wine grapes: Composition and quality of their musks and wines. Cal. Agr. Exp. S128. 3111. 79+: 83 Ppe Arnold, W. N. 1963. Carbohydrates in grapes CSIRO, Ibrt. Res. Sec. Ann. Rep. 1962-63. Herbein, Victoria, Australia. 3“ pp. Ballinger, W. E., H. I. Bell and A. L. Kenworthv. 1958. Soluble solids in blueberry fruit in relation to yield and nitrogen con- tent cf fruiting-shoot leaves. Mich. Agr. Exp. Sta. Quart. Bul. 2+0 (4): 912-9lue L. J. Kushman, and J. 1“. Brooks. 1963. Influence of crop load and nitrogen applications upon yield and fruit quali- tiae’s cg Wolcott blueberries. Proc. Amer. Soc. Hort Sci. 82: 2 -2? e Beach, Frank 3., T. H. Parks, and C. C. Allison. 1944. Grape growing in Ohio. Ohio Agr. Ext. Ser. Bul. 250: 1&7 pp. Beattie, J. 14., and H. P. Baldauf. 1960. The effect of soil management system and differential nitrogen fertilisation on yield and on the quality of Concord grape Juice. Ohio Agr. he she R08. Bnl. 8683 35 ppe Bioletti, F. 'r.. w. v. Cruess, and a. Devi. 1918. Changes in the chemical composition of grapes during ripening. Univ. Calif. Pubs. Agr. Sci. 3: 103-130. Brown, Dillon 3. 1952. Climate in relation to deciduous fruit pro- duction in California. V. The use of temperature records to pre- dict the time of harvest of apricots. Proc. Amer. Soc. Hort. Sci. 60: 197-203. . 1953. Climate in relation to deciduous fruit pro- duction in California. VI. The apparent efficiencies of differ- ent temperatures for the development of apricot fruit. Proc. Amer. Soc. Bert. Sci. 173-183. Bukovac, M. J., R. P. Larsen, and H. K. Bell. 1960. Effect of gibberellin on berry set and development of Concord grapes. Mich. Agr. Exp Sta. Quart. Bul. 1&2 (3): 503-510. 66 13. 1h. 15. l6. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 6? Bukcvac, H. J., .R. P. Larsen, and W. R. Robb. 1961+. Effect of N, N-Dimethyl amminosuccinamic acid on shoot elongation and nutrient composition of Viti Labrusca L. Cv. Concord. Mich. _'%u Agr. Exp. Sta. Quart. Bul. (1;): 1188-1191:. Caldwell, J. S. 1925. Some effects of seasonal conditions upon the chemical' composition of American grape juices. Jour. Agr. Res. XXX: 11 3-1176. Clare, W. J., and V. P. Brummund. 1960. The effect of vine size on the production of Concord grapes balanced pruned. Proc. Amer. Soc. Hort. Sci. 78: 239-2144. and L. R. Bryant. 1957. The effect of certain climatic factors on the growth, production and maturity of the Concord grape. Proc. Wash. State Hort. Ass'n. 53: 92-9”. Cock, James A. 1960. Vineyard fertilisers and cover crepe. Cal. Agre he Sta. EXte 801's 1931.. 128e Coombe, B. G. 1960. Relationship of growth and development to change in sugars, auxins, and gibberellins in fruit of seeded and seedless varieties of Vitis m. Plant Physiol. 35: Capper, J. R., and J. E. Vaile. 1939. Response of American grapes to various treatments and vineyard practices. Ark. Exp. Sta. Bul. 378: 71) pp. Crane, J. 0., and J. B. Brown. 1950. Growth of the fig fruit, Maryann Mission. Proc. Amer. Soc. Hort. Sci. 56: 93-970 Dorsey, M. J ., and R. L. McMunn. 1926. The development of the peach seed in relation to thinning. Proc. Amer. Soc. Hort. Sci. 23: “OZ-(+13. . 1927. Relation of the time of thinning peaches to the growth of fruit and trees. Proc. Amer. SOC. &rte Scie 24: 221‘228e Diagnostic Techniques for Soils and Crops. 1998., edited by Hermine Brodel Kitchen. The American Potash Institute. Washington, D. 0. Ezekiel, Hordecal, and Karl A. Fox. 1959. Methods of Correlation and Regression Analysis--linear and Curvilinear. John Wiley and Sons, Inc., New York. Hale, C. R., and R. J. Weaver. 1962. The effect of develOpmental stage on direction of translocation of photosynthate. Hilgardia. 33! (3) = 89-131. Hamilton, Joseph. 1953. The effect of cluster thinning on maturity and yield of grapes on the Yuma Mesa. Proc. Amer. Soc. Hort. Sci. 62: 231-2314“ ‘ 27. 28. 29. 30. 31s 32. 33- Bhe 35. 36e 37. 38. 39.. 40. 41. 42. 43. 68 Harmon, F. N., and Elmer Snyder. 1944. Effect of cluster removal upon fruit of Vinifera grapes. Proc. Amer. Soc. Hort. Sci. 44: 309-311. Heincke, A. J., and N. F. Childers. 1937. The daily rate of photosynthesis...of a young apple tree of bearing age. Cornell Univ. Agr. Exp. Sta. Men. 201. Hendrickson. A. R., and F. J. Veihmeyer. 1950. Irrigation Experi- ments with grapes. Cal. Agr. Exp. Sta. Bul. 728: 31 pp. Kattan, A. A., J. W. Fleming, D. L. Littrell, and T. 0. Brown. 1963. Seasonal changes in the quality of Concord grapes. Ark. Fern. Res. 12:9. Kenworthy, A. L. 1960. Photoelectric spectrometer analysis of plant materials. Proc. Council Fert. Appl. 36: 39-50. Kertess, Z. I. 1944. The chemical composition of suturing New York State grapes. N. I. StateAgr. Exp. Sta. Tech. Bul. No. 274: 13 pp. Kimball, Keith, and Nelson Shaulis. 1958. Pruning effects on the growth, yield and maturity of Concord grapes. Proc. Amer. Soc. Hort. Sci. 71: 167-176. Kramer, Paul J ., and Walter S. Clark. 1947. A comparison of photosynthesis in individual pine needles and entire seedlings at various light intensities. Plant theiology 22: 51-57. Iarsen, R. P. 1955. Nutritional conditions of Concord vineyards - in Mchigan. Ph.D. Thesis. Mich. State University. Unpublished. . Unpublished data. , H. K. Bell and Jerry Handigo. 195?. Pruning grapes in Michigan. Mich. State Univ. Ext. Bul. 347: 16 pp. Lilleland, Omund. 1932. Growth study of the peach fruit. Proc. Amer. Soc. Hort. Sci. 29: 8-12. .. 1963. Growth study of the apricot fruit. 11.. The effect of temperature. Proc. Amer. Soc. krt. Sci. 33: 269-279. Meyer, Bernard 8., and Donald B. Anderson. 1952. Plant Plvsiology. D. Van Nostrand Company, Inc., New York. Miller, C. E., L. H. Turk, and H. D. Fcth. 1958. Fundamentals of Soil Science. 3rd. Ed. John Wiley and Sons, Inc., New York. Nitsch, J. P. 1953. The plvsiolog of fruit growth. Ann. Rev. Plant thsiol. 4:199. , C. Pratt, C. Nitsch and N. J. Shaulis. 1960. Natural growth substances in Concord and Concord Seedless grapes in relation to berry growth. Amer. Jour. Bot. 47: 56 -576. 69 44. Overcash, J. D. 1955. Pruning, cluster thinning, and potash fertilizer experiments with Concord and Delaware grapes growing on Dog Ridge rootstocks. Kiss. Agr. Exp. Sta. Tech,. Bul. 41: 35 pp. 45. Partridge, N. L. 1925. Growth and yield of Concord grape vines. Proc. Amer. Soc. Hort. Sci. 27: 84-87. 46. . 1929. The young vineyard. Mich. Agr. Exp. Sta. Cir. Bul. 124: 16 pp. 47. . 1930. The fruiting habits and pruning of the Campbell Early grape. Mich. Agr. Exp. Sta. Tech. : 48 pp. 48. . 1931. The effect of fruit production and fertilizer treatments on the maturity of Concord grapes. Proc. Amer. Soc. Hort. Sci. 28: 147-150. 49. . 1931. The influence of long pruning and thinning on the quality of Concord grapes. Proc. Amer. Soc. Hort. Sci. 28: 144-146. 50. , and J. O. Veatch. 1931. Fertilisers and soils in relation to Concord grapes in southwestern mchigan. Mich. Agr. Exp. Sta. Bul. 114: 24 pp. 51. Sharples, G. 0., R. H. Hilgeman, and R. L. Milne. 1955. The re- lation of cluster thinning and trunk girdling of Cardinal grapes to yield and quality of fruit in Arizona. Proc. Amer. Soc. Hort. Sci. 66: 225-233. 52. Shaulis, N. J. 1956. The sampling of small fruits for composition and nutritional studies. Proc. Amer. Soc. Hort. Sci. 68: 576-585. 53. , and T. D. Jordan. 1960. Cultural practices for N.Y. vineyards. Cornell Ext. Ser. Bul. 805: 35 pp. 54. , and Willard B. Robinson. 1953. The effect of season, pruning severity, and trellising on some chemical characteristics of Concord and Fredonia grape juice. Proc. Amer. Soc. Hort. Sci. 62: 214-220. 55. Shoemaker, J. S. 1955. Small-Fruit Culture. McGraw-Hill Book Company, Inc., New York. 56. Sites, J. W., and H. J. Reitz. 1949. The variation in individual Valencia oranges from different locations of the tree as a guide to sampling'methods and spot-picking for quality. I. Soluble solids in the juice. Proc. Amer. Soc. Hort. Sci. 54: 1-10. 57. Snyder, John C., and David H. Brannon. 1961. Growing grapes in Washington. Wash. State Univ. Ext. Bul. 271: 26 pp. 1‘" fi‘ _J"'\.__ 58. 59. 60. 61. 62. 63. 65. 66. 67. 68. 69. 70. 71s 70 Swanson, C. A., and E. D. El-Shishing. 1958. Translocation of sugars in the Concord grape. Plant Physiol. 33: 33-37. Taylor, 0. C., and A. E. Mitchell. 1956. Soluble solids, sugar content and weight of the fruit of the sour cherry (Prunus cergsus) as affected by pesticide chemicals and time of harvest Proc. Amer. Soc. Hort. Sci. 68: 124-130. Tukey, H. B. 1936. Development of cherry and peach fruits as affected by destruction of the embryo. Bot. Gas. 98: 1-24. Tukey, Loren D. 1958. Effects of controlled temperature following bloom on the berry development of the Concord grape (Vitis Lab usca . Proc. Amer. Soc. Hort. Sci. 71: 157-166. Upshall, W. H., and J. R. van Harrlem. 1933. Yield and quality of fruit from strongly vegetative Concord grape vines. Sci. Agr. 14: 438-440. Vardis, Yoash, and A. N. Kasimatis. 1961. Vineyard irrigation trials. Amer. Jour. of Enol. and Viti. 17: 88-98. Weaver, Robert J. 1952. Thinning and girdling of Red Halaga grapes in relation to size of berry, color, and percentage of total soluble solids of fruit. Proc. Amer. Soc. Hort. Sci. 60:, 132-114’0 e . and Stanley B. McCune. 1960. Effects of overcropping Alicante Bouschet grape vines in relation to carbohydrate nutri- tion and development of the vine. Proc. Amer. Soc. Hort. Sci. 75 3 Sal--353 e Webster, J. E. and F. B. Cross. 1935. Use of the refractometer in studying sugar content of grape juice. Proc. Aner. Soc. Hort. Sci. 33: 444-446. . 1942. The uneven ripening of Con- cord grapes: Chemical and physiological studies. Okla. Agr. Exp. Sta. T0011. Bul. NO. T-Be Winkler, A. J. 1931. Prunin and thinning experiments with grapes. Cal. Agr. Exp. Bul. 519: 5 pp. . 1948. Maturity tests for table grapes - The relation of heat units summation to time of maturity and palatability. Proc. Amer. Soc. Hort. Sci. 51: 295-298. . 1962. General Viticulture. Univ. of Cal. Press, Berkeley and Ice Angeles, California. . and W. 0. Williams. 1936. Effect of seed development on the growth of grapes. Proc. Amer. Soc. Hort. Sci. 33: 430- 434. APPENDIX 72 APPENDIX TABLE I. Nutrient content of grape petioles. Survey vineyards, 1962. Vineyard Percent Parts per million number N K P Ca Mg Mn Fe Cu B Zn Mo 1 0.80 3.06 .235 0.90 0.21 890 62 12.9 20.8 28 0.2 2 0.86 1.00 .202 0.83 0.02 802 62 20.3 20.8 26 0.2 3 0.78 1.50 .193 0.98 0.06 236 62 12.9 26.0 30 0.6 0 0.82 1.96 .218 0.87 0.06 100 07 7.6 19.0 15 0.0 5 0.92 2.22 .250 0.83 0.00 337 53 83.0 23.6 20 0.0 6 1.00 2.70 .260 0.73 0.31 188 57 02.0 19.0 19 3.2 7 0.82 2.00 .159 0.91 0.37 380 56 10.2 20.2 28 0.0 9 0.88 1.10 .205 0.87 0.38 1193 102 92.0 21.3 39 3.8 10 0.92 1.96 .001 0.98 0.52 1193 85 88.2 27.2 30 0.6 11 0.90 2.00 .300 0.77 0.22 1193 56 12.9 23.6 30 3.0 12 0.98 2.00 .235 0.80 0.35 1102 69 12.0 23.6 36 3.6 13 0.88 1.60 .210 0.83 0.33 286 50 12.0 21.3 28 0.0 10 0.92 1.60 .002 0.98 0.53 151 53 12.9 20.8 2 0.6 15 0.80 1.21 .193 0.90 0.08 366 37 55.5 21.3 22 0.6 16 0.92 1.50 0227 1.02 0.08 200 50 56.6 22.5 28 0.8 17 0.62 0.98 .235 0.83 0.02 568 56 63.0 20.2 28 3.8 18 0.90 1.50 .392 0.91 0.59 80 91 15.6 21.3 20 0.0 19 0.80 1.76 .260 0.90 0.38 67 56 13.7 21.3 22 0.6 20 0.86 1.50 .250 0.73 0.02 231 30 27.1 20.2 20 3.6 21 0.76 1.00 .227 0.91 1.00 177 31 19.5 21.3 28 0.2 22 1.00 0.80 .317 1.02 0.00 119 00 10.2 22.5 20 5.0 2 0.88 1.00 .159 1.06 0.38 263 53 13.7 21.3 30 0.8 20 0.80 1.70 .350 1.10 0.29 270 66 12.0 20.8 28 5.2 26 0.70 1.50 .282 0.77 0.21 1167 50 111.0 20.8 30 3.6 28 0.78 1.96 .392 0.98 0.03 297 07 100.8 29.5 36 0.0 29 0.78 1.36 .210 0.91 0.29 310 88 02.0 23.6 30 0.0 30 0.72 1.86 .260 0.83 0.20 390 100 57.8 23.6 30 0.8 31 0.68 0.76 .227 1.10 0.66 516 72 68.2 28.3 30 5.6 32 0.68 1.10 .180 1.10 0.52 193 111 103.5 23.6 28 5.0 33 1.00 0.72 .180 1.18 0.60 008 00 15.6 29.5 38 5.6 30 0.72 2.08 .193 0.91 0.22 595 66 50.0 27.2 30 0.6 35 0.68 1.50 .336 1.10 0.35 291 75 78.0 20.8 30 5.8 36 0.60 1.00 .180 0.98 0.15 1193 72 186.8 23.6 01 0.8 37 0.78 1.70 0290 1.18 0.57 633 07 139.8 23.6 38 5.2 38 0.70 0.98 210 1.10 0.00 881 85 12.9 23.6 01 0.8 39 0.58 0.38 .102 1.06 0.68 380 111 12.9 26.0 30 5.0 00 0.72 2.22 .205 1.22 0.21 627 98 12.9 28.3 36 6.0 01 0.70 1.86 .235 1.18 0.31 202 56 11.0 30.3 30 6.0 02 0.60 0.72 .120 1.18 0.60 215 78 11.0 27.2 00 5.2 03 0.60 1.10 .235 1.00 0.05 71 50 12.9 30.3 07 6.2 00 0.60 1.10 .112 1.06 0.03 360 85 15.6 28.3 1 0.8 05 0.70 1.10 .168 0.90 0.03 528 72 17.6 21.3 36 0.2 06 0.66 2.08 .218 1.10 0.38 595 30 17.6 23.6 30 0.8 07 0.60 1.10 .193 0.90 0.53 777 50 111.0 20.2 30 0.8 08 0.60 0.92 .392 0.98 0.06 303 75 139 8 20.8 01 5.0 APPENDIX TABLE I. mrv 3;: -—m ,_.__‘ —~ 421-:- -——-——‘v -—n—g c- _ - m Continued. 73 Vineyard Pergent Pagtggger million number N K P Ca Mg Mn Fe Cu B Zn Mo 09 0.60 1.10 .136 0.98 0.29 209 56 18.5 23.6 30 0.8 50 0.62 0.76 .235 0.90 0.02 633 56 20.2 20.8 30 0.0 51 0.68 1.50 .159 1.06 0.30 906 78 20.2 27.2 00 0.6 52 0.68 2.22 227 1.10 0.23 100 69 23.2 30.7 50 5.0 53 0.56 1.10 .202 1.06 0.50 200 56 11.0 21.3 30 5.0 50 0.66 1.76 .159 0.90 0.25 252 00 7.6 20.8 28 0.0 55 0.96 1.00 .151 1.00 0.72 378 53 92.0 20.8 36 6.7 56 0.80 1.21 .102 1.18 0.66 252 37 05.6 26.0 30 5.6 57 0.80 1.96 .136 1.06 0.52 120 50 51.0 27.2 30 5.0 58 0.63 1.90 .159 0.88 0.25 205 29 2.5 20.6 19 0.0 59 0.60 2.22 0136 1.10 0.30 269 1 11.0 23.6 30 5.2 60 0.60 2.15 .380 1.21 0.20 173 69 8.3 32.3 19 5.2 61 0.86 2.08 .690 0.95 0.18 365 39 5.6 27.8 12 0.1 62 0.66 1.70 .022 0.98 0.37 302 69 12.0 27.2 30 5.0 63 0.56 1.00 .011 0.90 0.30 390 75 12.0 20.8 36 5.0 60 0.50 0.92 .136 0.91 0.21 202 53 8.0 22.5 36 0.6 65 0.58 0.60 .151 1.22 0.53 236 37 10.2 26.0 36 5.8 66 0.60 0.60 .168 1.06 0.53 320 00 9.3 20.8 28 5.0 67 0.76 1.50 .136 0.83 0.37 291 98 12.0 20.8 01 0.2 68 0.68 1.96 .168 0.80 0.22 350 56 10.2 20.8 28 3.8 69 0.70 0.76 .260 1.31 0.52 02 56 90.7 30.3 50 6.0 70 0.70 1.36 .202 1.22 0.05 63 00 122.0 30.7 07 6.5 71 0.66 1.36 .159 1.18 0.30 390 07 10.2 29.5 00 5.6 72 0.66 1.76 .202 1.10 0.20 225 30 25.1 29.5 30' 5.0 73 0.80 0.72 .120 1.10 0.50 85 07 38.8 30.7 36 5.2 70 1.02 3.26 .128 1.10 0.12 136 07 122.0 26.0 36 5.0 75 0.60 0.80 .282 0.98 0.33 1150 72 36.0 27.2 01 0.0 76 0.72 0.88 .168 0.90 0.22 008 50 33.0 23.6 36 5.0 78 0.76 1.96 112 1.22 0.28 177 00 90.6 29.5 50 5.2 79 0.62 1.21 .180 0.98 0.30 595 30 88.2 26.0 00 5.0 80 0.58 1.21 .308 0.90 0.30 225 30 126.8 20.8 01 0.0 81 0.92 1.70 .102 0.91 0.29 378 25 16.6 22.5 30 0.2 82 1.02 1.60 .136 1.06 0.35 33 30 10.2 26.0 36 0.6 83 0.80 0.92 .136 1.10 0.59 308 30 11.0 27.2 38 5.2 80 0.70 0.98 .168 1.10 0.06 258 37 15.6 23.6 36 0.8 85 0.70 1.36 .120 1.06 0.37 198 18 02.0 27.2 38 0.2 86 0.72 1.30 .105 1.22 0.52 077 30 53.0 26.0 07 6.0 87 0.76 0.08 .151 0.98 0.72 332 31 28.0 26.0 36 5.0 88 0.78 0.30 .136 1.22 0.03 1128 66 37.0 20.8 01 6.2 89 0.72 1.50 .128 1.10 0.00 162 28 139.8 29.5 07 6.0 90 0.82 0.80 .112 1.00 0.57 50 07 173.8 29.5 60 6.9 91 0.80 1.00 .102 0.90 0.37 380 31 18.7 28.3 38 0.6 92 0.90 2.52 .136 0.98 0.13 933 25 13.7 26.0 50 0.0 93 0.50 1.21 .392 1.26 0.70 30 50 33.0 31.9 01 6.0 90 0.68 2.22 .136 1.26 0.28 50 30 38.0 35.6 01 5.2 95 0.70 1.76 .099 1.02 0.22 58 30 181.8 30.7 38 5.0 _ 70 APPENDIX TABLE I. Continued. V1neyard _"_, lfggggnt Parts per million n um oer N K P Ca Mg Mn F a Cu B Zn Mo 96 0.56 1.36 .336 1.02 0.38 200 30 189.8 30.7 38 5 0 97 0.60 2.08 .520 1.06 0.20 528 25 12.0 29.5 36 4.8 98 0.58 0.98 .411 1.06 0.45 390 28 11.0 27.2 38 5.2 99 0.52 0.50 .151 0.94 0.70 348 91 10.2 23.6 36 5 O 100 0.62 1.21 .299 1.02 0.35 145 44 14.7 24.6 5.0 75 APPENDIX TABLE II. Nutrient content of grape shoot tips. Survey vineyards, 1962. Vineyard Percent Parts per million number N K P Ca Mg Mn Fe Cu B Zn Mo 1 2.56 2.08 .392 0.87 0.23 172 130 27.1. 23.6 07 0.2 2 2.68 2.08 .022 0.70 0.29 105 200 26.1 27.2 01 3.2 3 2.72 2.08 .392 0.77 0.26 71 75 19.5 20.8 00 3.6 0 2.60 1.96 .001 0.77 0.29 63 85 21.3 26.0 01 3.6 5 2.80 2.12 .052 0.58 0.26 85 82 31.0 20.8 00 3.0 6 2.50 2.08 .001 0.67 0.28 90 98 05.6 19.0 07 3.2 7 2.78 1.76 .363 0.60 0.28 80 69 19.5 21.3 38 3.0 8 2.66 1.70 .350 0.73 0.25 110 111 28.0 20.2 00 3.8 9 2.90 1.95 .032 0.70 0.25 167 82 27.1 22.5 00 3.8 10 3.20 1.96 .022 0.70 0.23 302 78 20.2 19.0 38 0.0 11 2.76 2.08 .022 0.55 0.25 350 262 32.0 20.8 60 2.8 12 2.92 1.86 .300 0.60 0.29 151 238 29.0 22.5 00 3.6 13 3.22 1.86 .001 0.70 0.26 90 102 29.0 22.5 00 0.0 10 3.20 2.12 .052 0.60 0.25 58 88 20.2 21.3 01 3.2 15 2.82 1.86 .022 0.67 0.26 90 88 106.2 21.3 36 3.6 16 2.86 2.08 .032 0.60 0.25 67 78 90.6 21.3 38 3.0 17 2.60 1.86 .363 0.70 0.29 85 102 *222.8 20.2 38 0.0 18 3.20 2.12 .060 0.60 0.29 50 259 27.1 23.6 00 3.0 19 3.06 2.12 .001 0.70 0.22 50 110 27.1 19.0 00 0.2 20 3.12 1.96 .001 0.60 0.29 67 56 29.0 19.0 38 3.2 21 2.78 1.96 .022 0.67 0.25 67 72 25.1 21.3 38 3.0 22 3.10 1.96 .032 0.60 0.26 50 59 22.2 21.3 01 3.8 23 2.70 2.12 .001 0.67 0.22 63 106 23.2 23.6 01 3.0 20 2.08 2.12 .032 0.61 0.23 67 66 19.5 22.5 00 3.0 25 2.38 2.34 .501 0.77 0.26 85 72 25.1 27.2 50 0.0 26 2.68 1.96 .001 0.58 0.23 220 66 59.0 21.3 01 2.8 27 2.60 2.08 .022 0.61 0.22 90 75 65.8 20.8 30 2.8 28 2.70 1.96 .060 0.09 0.25 58 56 62.2 31.9 30 2.6 29 2.78 1.96 .022 0.60 0.22 80 186 29.0 20.8 00 3.0 30 2.08 1.86 .022 0.60 0.22 99 277 35.0 20.8 30 3.2 31 3.20 2.08 .510 0.67 0.22 76 111 25.1 26.0 28 3.6 32 3.20 1.86 .530 0.67 0.23 58 82 22.2 21.3 30 3.0 33 2.60 1.96 .001 0.70 0.18 76 91 22.2 27.2 20 3.8 30 2.66 2.08 .022 0.58 0.22 85 128 28.0 23.6 28 2.0 35 2.80 1.96 .022 0.61 0.22 67 102 29.0 19.0 30 3.2 36 2.70 1.70 .382 0.77 0.21 252 137 119.5 22.5 25 0.0 37 2.90 2.12 .052 0.55 0.21 67 62 29.0 20.2 20 3.0 38 2.80 1.96 .060 0.61 0.20 99 110 20.2 22.5 20 2.6 39 2.78 1.76 .081 0.70 0.26 80 106 20.2 20.8 26 3.0 00 2.70 1.76 .081 0.61 0.21 119 82 22.2 17.9 20 2.6 01 2.78 2.08 .060 0.60 0.21 63 69 17.6 23.6 20 3.0 02 2.86 2.08 .091 0.55 0.21 02 95 22.2 22.5 28 3.0 03 ‘ 2.96 2.22 .091 0.55 0.20 26 75 21.3 23.6 20 2.6 00 3.12 1.86 .081 0.61 0.22 63 75 21.3 22.5 28 3.2 05 2.66 2.12 .001 0.61 0.23 90 95 22.2 23.6 30 3.0 76 APPENDIX TABLE II. Continued Vineyard Percent Parts per million number N K P Ca Mg Mn Fe 00 B Zn Mo 06 2.76 2 22 .002 0.52 0.22 63 62 18.5 21.3 20 3.2 07 2.66 2.12 .002 0.55 0.23 85 100 56.6 20.2. 01 2.6 08 2.62 1.96 .071 0.60 0.26 63 75 50.0 23.6 28 1.9 09 2.70 2.12 .071 0.58 0.22 50 75 17.6 20.8 28 3.2 50 2.66 2.22 .052 0.58 0.22 76 66 17.6 22.5 28 2.6 51 2.68 2.22 .052 0.09 0.22 100 153 20.3 20.8 30 2.2 52 2.96 2.22 .052 0.52 0.21 02 153 21.3 20.8 30 2.8 53 2.02 1.96 022 0.61 0.22 76 91 20.3 23.6 30 3.2 50 2.60 2.12 .363 0.60 0.25 06 95 15.6 21.3 26 3.0 55 3.10 2.08 .011 0.55 0.20 63 07 76.8 20.8 20 3.0 56 2.72 2.30 .032 0.52 0.23 50 00 82.0 28.3 28 3.0 57 2.92 2.22 .052 0.55 0.23 38 07 22.2 20.8 28 3.0 58 2.80 2.12 .060 0.61 0.23 58 59 ~ 15.6 22.5 28 3.0 59 3.00 2.12 .060 0.55 0.22 63 50 19.5 20.2 26 3.0 60 3.00 2.12 .071 0.67 0.22 50 75 16.6 26.0 28 3.0 61 2.76 2.22 .501 0.09 0.25 67 103 19.5 22.5 20 2.8 62 2.92 2.30 .530 0.52 0.22 71 166 17.6 22.5 20 2.0 63 2.58 1.96 .032 0.55 0.22 71 106 -17.6 20.2 07 3.0 60 2.10 1.50 .336 0.80 0.28 100 186 10.7 26.0 30 0.2 65 2.72 1.96 .002 0.61 0.22 58 72 17.6 23.6 28 3.0 66 2.78 1.96 .081 0.61 0.25 76 88 10.7 27.2 28 3.0 67 3.00 2.22 .032 0.06 0.22 58 183 28.0 22.5 30 2.6 68 2.52 2.12 .071 0.55 0.25 99 110 23.2 20.8 30 3.0 69 2.32 1.30 .317 0.90 0.26 38 137 238.8+ 33.0 28 5.6 70 2.72 1.70 .300 0.73 0.22 38 121 238.8+ 26.0 20 0.2 71 2.02 1.76 .011 0.60 0.22 90 53 17.6 20.8 28 3.0 72 2.78 1.96 .052 0.61 0.20 50 75 18.5 22.5 20 3.0 73 2.00 1.86 .372 0.67 0.29 30 78 238.8+ 28.3 28 3.8 70 2.26 1.76 .392 0.60 0.20 58 75 50.0 22.5 28 3.6 75 2.70 2.08 .011 0.61 0.20 129 118 35.0 27.2 28 3.8 76 2.56 2.08 .411 0.67 0.21 85 102 29.0 26.0 28 3.8 77 2.50 2.08 .392 0.52 0.22 63 69 29.0 22.5 26 '3.0 78 2.60 1.50 .336 0.67 0.20 50 88 97.2 26.0 22 3.6 79 2.08 1.60 .372 0.60 0.25 100 102 *152.8 28.3 20 3.2 80 2.38 1.70 .022 0.61 0.26 71 66 *162.8 27.2 20 3.2 81 2.80 2.12 .002 0.61 0.23 99 82 20.3 22.5 30 3.0 82 2.58 1.76 .052 0.55 0.22 76 110 20.3 23.6 30 2.8 83 3.06 2.08 .071 0.58 0.25 50 56 19.5 23.6 26 3.0 80 2.00 1.86 .022 0.52 0.23 50 121 23.2 22.5 28 2.8 85 2.50 1.86 .001 0.55 0.21 50 59 21.3 23.6 20 3.0 86 2.08 1.60 .336 0.61 0.22 63 91 30.0 26.0 26 3.0 87 2.36 1.76 .002 0.52 0.23 50 59 19.5 23.6 20 2.6 88 2.28 1.00 .350 0.61 0.20 100 137 33.0 21.3 26 3.0 89 2.02 1 96 .392 0.58 0.22 02 56 103.5 26.0 28 3.0 77 APPENDIX TABLE II. Continued Vineyard Percent Parts per million number N K P Ca Mg Fe Cu B Zn Mb 90 2.60 1.60 .392 0.67 0.22 26 85 *102.8 23.6 26 3.0 91 2.06 1.70 .372 0.52 0.21 85 66 10.7 23.6 22 2.6 92 2.52 1.96 .032 0.55 0.20 162 78 15.6 23.6 30 3.2 93 2.26 1.60 .363 0.60 0.28 22 110 29.0 28.3 26 3.6 90 2.16 1.76 .326 0.67 0.23 38 72 22.2 28.3 26 0.2 95 2.00 1.86 .363 0.67 0.28 02 128 238.8+ 29.5 30 0.2 96 1.86 1.50 .282 0.80 0.30 67 180 238.8+ 30.7 26 0.0 97 2.06 2.22 .011 0.60 0.21 129 85 22.2 20.8 28 3.0 98 2.62 1.96 .372 0.61 0.25 90 72 22.2 20.8 20 3.0 99 2.00 1.50 .290 0.70 0.28 71 153 20.3 23.6 17 3.8 100 2.00 2.08 .336 0.67 0.23 63 211 21.3 20.8 26 3.8 f base satur- ation saturation & k K Survey vineyards, 1962. CEO 0 78 Ca K Soil analysis. lbs./acre - avail. P Soil number texture pH APPENDIX TABLE III. Vine; yard 5203836£Oonvonvo 28673166148479306075903350 BIO. 54 2/0.” 5% m%W&&%885&W&WW%%%WW%/Mmm33m 8%.Dfifi .mfi,,m%57..fl&.8 27.522898590326525002711754003613.461006689734 ccccc l 2222 .4 132211o4 12 8008636593505599630206716206086875840031566 2 8003/087.0/7.7797958630912976727056057252032567 45466551111456656666732 32256316 34.41255 35& .4227711510072203.4506264638831380606008301154.4 ooooooo 580634619203337910098 54690060923942255598164 424332243545324353333985mnm2334262422116m421 2000286100102 860 600600 060382 0127710883 38818 764 669&%%865%686 56%6789 3m86322541 8 21R1 4 11 211 1 1411 11 fl 1n 5181548 8 688882 03388000140505 600 220 .466 l 11 11 1 0646208 088 2 2 0080 288/086 808862680006 2 1 11 112 11 1211E2 le3311111321 1 RRIZZ arm/$02 73 9 2 8916 30 4182965204 608 53595 llllllwmln 1M 31% l M 1 1111 61R1 Hull 90946344424056306423459633247632566760386535 :JAchAuAuAuAu(JazzazzAuAuAuAuAuAVAUAUACAVczzzhwchzconAchcjgunw:JszJhwzchanchAuAu nw221404cijzchanwhwhwc21462h4nw:JzJQJQJQJoanoaogeazucjzanw:annwszJ:J:2:5929211:):5 01 1111119 0:2 :22 :33 33333334444 4.4.4 i base Lam satur- Mg ation Ca K M8 .0530 79 Ca Continued K P lbs.[acre - av§;;, Soil APPENDIX TABLE III. number texture pH Vine- yard 6354594 7.8172576440108342931482956389817600528 oooooooooooooooo Imp/“87.5.29 9 5 52966189/nwnh934991m382630n 2305 9 35720672113828061088287204935825018181105924 0009870963246 73910355533861.0126 95237641405007 oooooo 0000377690869L327099191 l/OolszJRw .69 ./O.3Rwh~w5rth/.7w55 53223737672777555871358 36636.4 53 568741582 32088233971064327473102958507172006383665222 OOOOOOOOOOOOOOOOOO 3.4.335nh5k334 5.4.64anvohw3433554 27560.4 756 564431654 2 00044649376449074591919766496496967328150762 ooooooooooooooooooooooooooo 1 80 801 831188300211678312630480 888101626 0 11 l l 21 2.1. 212 111 21 111 111 31 21 11 111 1.... 12 00868826 260042088 0 82 60282 6 28800252064 21352211 1112le.0“ 1232222332524321122 3222 yawmmywwnmm%u%%%wwwnwmwfimwmamfimwwaarwrmw%mww 2Rwhfi59085465/334oonW5586528ndJQ/1498 583.4...0.nw52.4.Ru./nw5n/.1 0 ID. 5544... 75/066 SS/Oo/nw/O/O/O/O/O 55665556” 555555/hw/hw6/nw6 :Jhwd 56.4..4n .440 555 55555666666 :666 :77 7.77 57778888 88888999 80 APPENDIX TABLE III.— Continued Vino-' fl base yard Soil lbs,[acre - avail. fl satggasggn satur- number texture pH P K CI Hg CEO I Ca Mg ation 93 4 7.2 37 688 3120 400 10.2 8.6 76.4 15.6 99.9 ‘94 a 6.3 9 288 1488 112 4.9 7.3 75 5 8.1 89. 7 95 4 5.8 123 128 624 62 3.8 4.27 39. 4 5.2 47.3 96 2 5.9 77 200 1248 224 8.2 3.0 37.8 10.9 51.2 97 u 5.4 75 136 671 no 4.8 3.5 33 3 2.0 37.5 98 4 5.9 55 160 1200 61 3.9 5.1 76.9 5.1 87.1 99 5 6.7 142 72 863 182 2.9 3.1 72. 4 24.1 96. 5 100 5 7.0 123 80 1248 128 3.7 2.7 83.7 13.5 99. 9 81 APPENDIX TABLE IV. Row spacing, trellis height, vigor rating, clusters per vine and soluble solids. Survey vineyards, 1962. Vineyard Row spgcing - ft. Trellis Vigor Clusters/ Soluble number within between height rating vine solids - f 1 10.0 8.0 4.83 4 88 16.0 2 10.0 11.0 4.17 4 92 16.5 3 8.0 10.0 4.14 3 102 17.5 4 7.5 8.0 5.00 n 86 16.5 5 8.0 9.0 5.50 4 65 17.5 6 8.0 10.0 4.50 4 55 17.0 7 8.0 9.5 4.17 3 71. 17.0 9 8.5 8.0 4.83 3 78 16.5 10 705 705 1‘01? 3 63 1605 11 8.0 8.0 4.50 4 82 16.0 12 8.5 10.0 4.33 3 98 16.5 13 8.0 10.0 5.67 3 142 15.0 14 8.0 9.5 5.33 4 120 15.5 15 8.0 8.0 4.50 4 82 16.0 16 8.0 10.0 4.67 4 67 15.5 17 10.0 10.0 4.67 2 74 17.5 18 10.0 9.5 4.83 4 88 15.0 19 10.0 10.0 5.33 4 88 16.5 20 9.0 10.0 4.83 3 116 17.0 21 8.5 9.5 4.33 4 9° 17.0 22 7.5 9.5 4.67 3 48 17.0 23 7.5 9.0 4.50 3 58 17.0 24 9.0 9.2 4.71 4 70 15.0 26 10.0 9.0 4.50 3 82 15.5 28 10.0 8.0 4.33 4 >72 15.0 29 8.0 9.0 5.33 5 63 16.0 30 9.0 9.5 5.00 4 68 15.5 31 8.0 9.0 5.17 3 47 18.0 32 9.0 10.0 5.00 4 123 16.0 33 10.0 8.5 4.50 4 64 17.0 34 9.0 9.5 5.00 4 87 15.0 35 10.0 9.5 4.83 2 67 17.0 36 9.0 10.0 5.00 4 123 16.0 37 10.0 9.5 4.67 3 84 16.5 38 8.0 10.0 4.50 3 83 17.0 39 8.0 10.0 4.50 2 92 17.5 40 10.0 10.0 4.50 3 88 17.0 41 8.0 10.0 4.67 3 70 18.5 42 12.0 10.0 4.00 2 112 17.5 43 8.0 8.0 4.50 4 90 15.5 44 9.0 9.0 5.00 3 123 15.0 45 9.0 9.0 4.83 4 75 16.5 & mmumd AWWMXMfiEN. Sflwh wh®-$ Clusters/ fim mum Trellis Vigor height 6 -fi mumn mws within nmmr Vineyard 055550555.5005&050055550005005550500JJJJ5JO5£O 9 O O O O O O O O O O O O O O O O O O O O O O O O O 77557575566557679 7555 75 85366 5665 6665 W11111111111111111N1111m11MM11111M1lllwllllmm 8 39. 1 39317 5 95060 001808239298918 295 5&00m%fl7 1 01&9%%WW 91 0&31706 0 6863 0%903 11 1 Blull R 1M1 11 11R14 lflflll 11 332 55332533444. 3332 33.4 52 23354 24. 2 23553353334. 24.“. 73007330777707003w/0770007030737770073330300 73 685016.30.6.66lo.1“0.56. 011055653013166086383035013 O o O 0 O O O 0 44455445444554 5444545544445554444544445444544 500554000500000045050050550055022005500000000 800999080900008099990078899899899009989998898 ll 1 l 1111 1 ll 11 5050000500000000010050000000055077000500000000 . 809009878887888999090820 n8m99888668601900978 1 ll 1 1 ll 11 ll 83 APPENDIX TABLE IV. Continued Vineyard Row'sggcigg - ft Trellis Vigor Clusters] Soluble number within between height rating vine solids - f 93 9-5 9.0 4.83 2 77 17.5 94 9.5 9.5 4.83 3 74 16.5 95 10.0 10.0 5.00 3 92. 17.0 96 10.0 9.5 4.50 1 56 19.0 97 10.0 8.0 4.50 4 100 15.5 98 10.0 8.0 4.67 4 112. 15.0 99 9.5 9.5 5.17 3 114 18.5 100 9.5 9.5 4.50 4 109 16.5 APPENDIX TABLE V. Nutrient content of grape petioles. Survey vineyards, 1963. Vineyard __ Percent Parts Qer million number N X P Ca Mg Mn Fe Cu B Zn 6 1.34 3.20 .159 0.87 0.35 177 41 242.9 27.2 31 9 1.12 1.62 .210 1.14 0.92 7011 88 12.9 30.7 85 12 1.34 3.30 .264 0.80 0.34 753 95 46.7 29.5 60 15 0.96 1.80 .299 1.10 0.62 484 85 48.8 30.7 83 17 1.00 2.14 .290 0.94 0.37 484 62 13.7 26.0 67 24 1.04 2.22 .392 1.22 0.37 215 137 12.0 34.3 95 .25 0.98 2.14 .392 1.10 0.33 177 153 12.0 34.3 95 28 0.96 2.22 .382 1.06 0.43 396 62 29.0 34.3 95 29 0.94 1.74 .264 1.18 0.40 258 53 41.2 33.0 91 33 1.08 0.86 .235 1.14 1.17 177 59 15.6 27.2 71 38 1.00 1.52 .245 1.06 0.52 440 37 10.2 24.8 64 40 1.18 2.82 .471 1.44 0.29 634 75 15.6 29.5 79 41 1.20 3.10 .401 1.40 0.37 204 82 15.6 31.9 87 42 1.16 1.68 .151 1.31 0.60 151 111 15.6 31.9 87 43 1.16 2.08 .245 1.06 0.40 46 66 13.7 34.3 95 44 1.16 1.88 .193 0.87 0.57 151 66 20.3 34.3 95 47 1.42 2.22 .254 0.91 0.40 384 88 120.8 28.3 54 51 1.22 2.48 .218 1.06 0.40 528 37 21.3 27.2 71 52 1.18 3.10 .254 1.14 0.29 71 56 38.0 31.9 87 54 1.04 2.74 .218 0.91 0.28 129 37 16.6 29.5 79 59 1.32 4.00 .254 0.94 0.26 129 47 19.5 29.5 79 63 1.04 1.80 .326 0.98 0.43 280 75 10.2 29.5 79 64 0.96 1.80 .273 1.18 0.38 269 91 12.9 33.0 91 65 0.94 1.94 .168 1.35 0.59 269 53 10.2 31.9 87 66 1.04 1.88 .151 1.35 0.64 263 59 12.0 31.9 87 67 1.22 2.38 .151 0.98 0.53 263 88 47.6 28.3 67 70 0.94 1.88 .184 1.31 0.60 119 44 9.3 31.9 87 73 0.82 2.82 .290 1.10 0.60 85 98 11.0 29.5 79 75 0.88 1.62 .227 1.18 0.45 806 50 19.5 28.3 75 79 0.88 1.68 .273 1.18 0.48 378 53 199.3 41.6 123 80 1.14 2.00 .530 1.06 0.43 204 111 210.0 34.3 67 81 1.46 3.00 .210 0.87 0.30 151 44 12.9 29.5 79 82 1.38 2.92 .290 0.80 0.31 156 53 16.6 26.0 67 87 0.92 0.94 .175 1.10 0.82 193 91 130.1 29.5 67 88 0.84 0.38 .159 1.22 0.66 568 72 158.4 27.2 64 89 1.10 1.94 .227 1.02 0.52 80 41 100.8 31.9 87 90 1.50 0.90 .168 1.10 0.68 80 34 204.6 24.8 64 91 0.96 0.90 .175 1.06 0.66 496 37 12.9 31.9 87 92 0.96 2.82 .151 1.06 0.17 556 37 15.6 31.9 75 93 1.04 1.74 .344 1.10 0.72 30 59 84.6 34.3 75 94 1.20 2.92 .159 1.18 0.30 50 47 73.1 33.0 79 95 1.16 2.82 .175 1.06 0.28 50 34 137.1 29.5 79 96 1.06 2.08 .227 1.22 0.34 188 75 190.3 34.3 95 99 1.16 2.08 .184 0.98 0.50 247 88 15.6 39.2 113 100 1.04 2.22 .382 1.18 0.53 134 75 14.7 27.2 36 $ base satur- ation saturation K Ca Mg Survey vineyards, 1963. 743' CEC % Ca K 1bs./acre - avail. Soil analysis. P Soil number texture pH APPENDIX TABLE VI. Vine- yard 57827375302497500449330029614433391312456612 eLmOKJQ/sn/ozmm 095.7611 6156183AU09315122 egz/nwl/nwaoo26lnh 329970859035056811.401100272284756238494598316 6n]. 660.67. 2825 8 0.02%65933/nw 5&237BQNn/6816138m.8 3 l 112 .4.. 46 2.1. DIV. 121 l 1 50992320405102215720926657648298858334464310 82701nu..46nw785 24140796866606695028371625829819 26 27367142 77321227156137322755887533437515 57447992315308801472665713338 BRW 22”..)167632384 ooooooooooo 39138380359855498811562643141777124923518258 . (Onénu.v 232MOF/o nUoZQ/AWZQJl who/1.46 $33 L133/nwano99nv6/Ol48 14 1 1 4 114 4 11 1 %w%wmmwsaswwmwwmumwwmmoaanwmnsnwnwmaasmmmmnm o 88 0268 8010802 00 82 o 106 1220 241121 800 nnwwwunmnwwwnmmmmnmmnwmmmwmuwnwommmmnnmnmmmw 1 111 l 2 11111 .1. 111211112 2 O 02 8 8 800080 2 8224882 80 0 6 o 8226 1 11 11222 1 32611 1 2111 1 1616 2 3 666 63 3 17 8766654 9466 8 1675311634 162 0837517855270512834568849.400093880100636 ”800$ 66 556666 56 ssh/9.6664556 56644 $666666/nw al.66556 56 556 55555554 2 2 2 24 55555533552 2 54 554 55554 2 2 2 2 33552 80 81 82 87 88 11111222223333.4444 44555 556 66667777 86 APPENDIX TABLE VI. Continued Vine- i base yard Soil 1bs.[acre - avail. i saturation satur- number texture pH P K Ca Mg CEO I Ca Mg ation 93 2 7.3 108 512 2080 224 6.7 9.7 77.6 13.4 99.9 94 4 6.4 9 344 1144 80 4.5 9.7 62.2 6.6 77.7 95 5 5.5 81 112 496 51 5.5 2.5 21.8 3.6 27.2 96 2 5.5 45 168 1456 224 7.7 2.7 46.7 11.6 61.0 99 5 7.0 142 72 728 160 2.4 3.7 75.0 25.0 99.9 100 5 7.2 136 88 1248 128 3.7 2.9 83.7 13.5 99.9 87 APPENDIX TABLE VII. Foliage density, vigor rating and soluble solids. Survey vineyards, 1963. Vineyard Fbliage Vigor Soluble number density rating solids - 5 3 48 3.0 16.57 6 80 4.0 15.60 11 70 4.0 15.35 12 60 3.5 16.19 15 65 4.0 14.74 17 43 3.5 15.89 19 85 4.5 14.98 21 78 4.0 13.78 24 35 2.5 15.36 25 38 3.0 15.14 28 100 4.5 13.14 29 98 4.0 13.14 31 38 3.0 15.57 33 35 3.0 16.19 38 40 3.0 16.72 39 30 2.0 16.98 40 40 2.5 16.01 41 45 3.0 16.65 42 40 2.0 15.79 43 35 3.0 15.69 44 40 3.0 15.61 47 58 3.0 16.64 48 28 2.0 17. 96 51 68 3.0 15. 34 52 60 3.0 15.70 53 33 2.0 16 .74 54 90 5.0 14.60 58 65 3.5 15 08 59 83 4.0 13.75 60 98 5.0 13.82 63 38 3.0 17.24 64 20 1.0 16. 74 65 60 3.5 15.12 66 75 4.0 14 .45 70 35 2.5 16 35 73 75 “.0 13. 9“ 75 65 3.0 14.95 79 25 1.5 15.50 80 43 3.0 15.11 81 100 5.0 12 96 82 100 5.0 14.06 87 70 3.0 15 51 88 APPENDIX TABLE VII. Continued Vineyard Foliage Vigor Soluble number density rating solids - f 88 38 2.5 15.62 89 83 4.0 16.01 93 28 2.0 16.30 9h 63 3.5 14.52 95 43 3.0 15.56 96 25 2.0 16.71 99 53 3.5 16.17 100 70 4.0 14.60 89 APPENDIX TABLE VIII. PBtiole nitrogen, yield.per vine, foliage density and soluble solids. Nitrogen study - Growers' vineyards, 1963 and 64. g r Vine- Treat- yard ment Nitrogen - i Yield - Foliage Soluble number nitrogen June July 1bs./vine density - f solids - f 58 + 1.74 1.38 1963 8.53 70 15.46 0 1.70 1.10 9.38 65 15.08 31 + 1.85 1.16 19.08 43 15.28 0 1.58 1.18 17.77 38 15.57 19 + 1.56 1.14 19.08 73 15.37 0 1.62 1.24 20.35 85 14.98 21 + 1.48 1.28 25.50 93 13.43 0 1.1“} 0.96 33.03 78 130% 39 + 1.24 0.92 14.43 35 16.24 0 1.22 0.90 10.55 30 16.98 60 + 1.84 1.46 23.18 100 14.03 0 1.63 1.14 18.93 98 13.82 11 + 2.18 1.44 9.85 73 15.61 0 2.00 1.12 11.08 70 15.35 53 + 1.46 0.94 14.20 43 16.96 0 1.37 0.84 16.73 33 16.74 3 + 1.80 1.30 6.55 40 16.97 0 1.63 1.14 14.29 48 16.57 48 + 1.70 1.40 9.07 40 17.88 0 1.37 1.14 9.41 28 17.99 1964 58 + 1.59 1.40 22.58 77 15.69 0 1.57 1.36 22.80 72 15.64 31 + 2.14 1.45 19.75 65 16.49 0 1.34 1.27 10.88 42 16.74 19 + 1.49 1.40 26.93 69 15.60 0 1.37 1.42 28.08 66 16.49 21 + 1.39 1.29 21.65 85 16.10 0 1.20 1.06 23.30 73 '16.07 39 + 1.28 1.21 19.45 51 16.62 0 1.09 0.86 17.63 35 16.39 60 + 1.66 1.51 19.48 87 15.26 0 1.19 1.33 19.98 83 14.89 11 + 1.67 1.52 12.13 68 16.76 0 1.37 1.32 12.10 67 16.88 53 + 1.30 1.15. 9. 73 38 15. 99 o 1.11 0.91 10.28 25 17.10 3 + 1.71 1.32 18.98 45 15.74 o 1.32 1.18 24.57 46 15.98 48 + 1.19 1.20 21.01 41 17.26 0 1.03 1.00 23.73 28 17.09 9O Petiole nitrogen, yield per vine, pruning weight and soluble solids. Nitrogen study - Sodus, 1963 and 1964. APPENDIX TABLE IX. Soluble Pruning - solids - fl lbs./vine Sawdust - Nitrogen - i Yield - NHQNO3 1bs./vine Rep June July lbs./vine 1963 0 0 I 1.09 0.89 14.2 16.31 4.25 10 1.02 0.79 15.1 16.66 2.25 20 1.08 0.75 17.9 16.42 3.08 o 0 II 1.10 1.01 9.0 16.87 1.83 10 1.02 0.81 18.7 16.75 2.33 20 1.14 0.95 19.9 16.73 3.58 0 0 III 1.18 1.04 18.5 16.25 3.75 10 0.99 0.88 22.7 15.95 3.00 20 1.11 0.83 23.2 16.39 3.67 0 0 IV 1.07 0.95 19.8 17.01 3.08 10 1.06 0.93 21.9 17.16 2.92 20 1.21 0.92 18.4 16.34 4.42 1 0 I 1.48 1.15 14.5 16.61 5.08 10 1.25 1.09 20.1 16.42 5.33 20 1.33 1.09 17.4 16.57 4.17 1 0 II 1.80 1.03 13.8 16.37 3.67 10 1.15 1.00 15.2 16.48 3.42 20 1.76 0.93 18.5 16.78 3.00 1 0 III 1.26 1.05 16.4 16.12 4.83 10 1.39 1.15 17.8 16.45 5.42 20 1.19 1.08 12.9 16.40 5.67 1 0 Iv 1.10 1.07 14.2 16.76 4.58 10 1.20 1.08 14.9 16.35 2.67 20 1.25 1.04 24.1 16.80 4.08 1964 o 0 I 1.41 1.37 15.7 16.73 10 1.16 1.42 21.0 16.26 20 1.25 1.15 16.2 17.10 91 APPENDIX TABLE IX. Continued Sawdust - Nitrogen - f Yield - Soluble NH4N03 1bs./vine Rep June July 1bs./vine solids - 5 0 0 II 1.33 1.23 17.7 16.03 10 1.12 1.03 15.2 16.90 20 1.20 1.15 23.4 16.63 0 0 III 1.11 1.47 26.9 15.67 10 1.17 1.39 24.9 16.43 20 1.31 1.29 22.0 16.37 0 0 IV 1.35 1.35 22.6 16.00 10 1 21 1.23 17.8 16.60 20 1.22 1.20 21.1 16.47 1 0 I 2.14 1.42 21.3 16.47 10 1.47 1.31 19.8 16.07 20 1.47 1.23 23.9 16.07 1 0 II 1.75 1.27 21.7 15.93 10 1.55 1.10 20.2 16.20 20 1.87 1.20 20.3 15.80 1 0 III 1.47 1.41 19.9 15.47 10 1.37 1.42 22.3 16.57 20 1.43 1.42 23.0 15.87 1 0 IV 1.50 1.28 24.7 15.87 10 1.66 1.39 18.9 15.23 20 1.61 1.36 23.4 16.53 APPENDIX TABLE X. Yield.per vine and.sclub1e.solids. 92 Shading studies, 1962. Yield.4. Soluble Shade Sub-treatment Rep lbs. /vine solids - 5 0 none I 24.0 9 15.0 shoots tipped 14.6 14.5 clusters thinned 7.7 17.0 0 none II 9.9 15.0 shoots tipped 20.5 15.5 clusters thinned 6.5 16.5 0 none III 25.8 15.0 shoots tipped 17.7 15.0 clusters thinned 13.4 16.5 0 none IV 12.0 16.0 shoots tipped 14.6 16.0 clusters thinned 6.1 16.5 30 none I 5.0 15.5 shoots tipped 14.3 15.0 clusters thinned 8.9 15.5 30 none II 8.4 16.5 shoots tipped 8.4 15.0 clusters thinned 8.1 16.5 30 none III 13.8 14.0 shoots tipped 13.5 15.5 clusters thinned 6.8 16.0 30 none IV 25.6 14.5 shoots tipped 15.7 14.0 clusters thinned 12.8 15.0 50 none I 6.7 15.0 shoots tipped 7.8 15.5 clusters thinned ‘5.5 15.0 50 none II 21.3 14.0 shoots tipped 13.0 14.5 clusters thinned 7.7 14.5 50 none III 14.6 14.5 shoots tipped 13.5 15.0 clusters thinned .8'1 16.0 50 none IV 5.4 15.5 shoots tipped 14.3 13.5 clusters thinned 7.9 15.5 93 APPENDIX TABLE XI. Yield per vine and soluble solids. Shading studies, 1963 and 64. Yield Soluble _Date Shade Rep lbs./vine solids - f 1963 6/17 to 8/7 0 I 7.5 15.16 30 9.9 14.58 50 4.3 16.21 0 II 9.0 14.62 30 ' 9.3 14.33 50 7.3 14.89 8/7 to 9/26 0 I 6.3 16.06 30 7.8 14.68 50 6.5 13.61 0 I 4.3 15.17 30 3.2 13.57 50 4.3 13.43 1964 6/19 to 8/7 0 I 3.8 16.04 30 12.6 15.65 50 5.2 16.39 0 II 14.3 16.37 30 10.8 15.30 50 7.8 14.44 8/7 to 9/24 0 I 13.8 17.14 30 8.3 13.36 50 8.7 12.95 0 II 8.7 16.50 30 9.0 13.59 50 6.6 14.60 {0 I . z '1 (373%.. "m 4 .’ \ ‘ A": ' n Y .‘ 3‘ Vs"! [1" . 4. ~ 1- “- i F’ 78:71.!” a? .7. ,‘j m, ' ‘r I (4891 ' ids" 3.8