THE EFFECTS OF ORGANIC FUNGICIDES, COPPER FUNGICIDES, AND TIME OF HARVEST ON SIZE, FIRMNESS AND CHEMICAL COMPOSITION OF FRUIT OF THE SOUR CHERRY (PRUNUS CERASUS L . ) By Oliver Clifton Taylor A THESIS Submitted to the School of Graduate Studies of Michigan State College of Agriculture and Applied Science in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Department of Horticulture Year 1953 ProQuest Number: 10008484 All rights reserved IN FO R M ATIO N TO A LL USERS The quality o f this reproduction is dependent upon the quality o f the copy subm itted. In the unlikely event that the author did not send a com plete m anuscript and there are m issing pages, these w ill be noted. Also, if m aterial had to be rem oved, a note will indicate the deletion. uest ProQ uest 10008484 Published by ProQ uest LLC (2016). C opyright o f the Dissertation is held by the Author. All rights reserved. T his w o rk is protected against unauthorized copying under Title 17, United States C ode M icroform Edition © ProQ uest LLC. ProQ uest LLC. 789 East Eisenhow er Parkw ay P.O. Box 1346 Ann Arbor, Ml 4 8 1 0 6 - 1346 ACKNOWLEDGMENTS The author wishes to express his sincere thanks to Dr. A. E. Mitchell for guidance and assistance in con­ ducting the research reported herein, and in the prepara­ tion of this thesis; to Dr. E. J. Benne and Miss E. Heinen for suggestions and assistance in making certain quanti­ tative determinations; to William J. McLachlan, Neil Morrison, Leo Settler and Floyd Fox for making their orchards available for this study; and to Dr« L. M. Turk of the Department of Soil Science, Dr. G-. P. Steinbauer of the Department of Botany and Plant Pathology, Dr. A. L* Kenworthy and Dr. II. B. Tukey of the Department of Horticulture for serving on the guidance committee0 THE EFFECTS OF ORGANIC FUNGICIDES, COPPER FUNGICIDES, AND TIME OF HARVEST ON SIZE, FIRMNESS AND CHEMICAL COMPOSITION OF FRUIT OF THE SOUR CHERRY (PRUNUS CERASUS L.) By Oliver Clifton Taylor AN ABSTRACT Submitted to the School of Graduate Studies of Michigan State College of Agriculture and Applied Science in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Department of Horticulture Year Approved 1953 An investigation was made during the period, 19^4-9 through 1952, to determine the effects of time of harvest and the effects of organic and Inorganic fungicides on the ohysical and chemical changes in the development of Mont­ morency cherry fruits (Prunus cerasus L.). Physical measurements included weight, transverse diameter, firmness of flesh and specific gravity of fruits, Chemical deter­ minations Included soluble solids, total solids and total sugar cont ent a In a detail study in 1951 and 1952 at the Michigan State College Horticulture Farm, East Lansing, the soluble solids content, total solids content, total sugar content and specific gravity of fruits increased significantly as the harvest season progressed* The most pronounced in­ creases occurred during the first two weeks of the prolonged harvest season. Highly significant positive correlations were found between the increases in soluble solids and total solids and between increases in soluble solids and total sugars as the harvest season progressed. The total solids and total sugar content of cherry fruits decreased Immediately following a rain, which occurred at approximately mid-harvest season. The average weight of fruits increased following the rain at mid-harvest season. The average transverse diameter of the cherries changed very little throughout the harvest period. The flesh of the fruit gradually became less firm during the first two weeks of harvest, after which time the firmness Oliver Clifton Taylo increased until the fruits began to shrivel on the trees. It was found also in this study that fruits from trees sprayed with fixed copper were lighter in weight and higher in soluble solids content than fruits from trees sprayed with ferbam. Fruits from trees sprayed with lead arsenate tended to be lighter in weight and higher In soluble solids than fruits from trees sprayed with parathion. There was evidence that the dry weather in 1951 and 1952 had a greater Influence than spray treatments on the weight of the cherry frui t s• In a second portion of this investigation made from 19ll9 through 1952 in five commercial orchards, trees of moderate vigor sprayed with fixed copper produced fruits lighter in weight than trees sprayed with ferbam or nabam. However, trees of very high vigor, sprayed with fixed copper produced as heavy or heavier fruits than trees of less vigor sprayed with ferbam or nabam. true during seasons of high rainfall. This was especially There was generally no difference in average weight of fruits between the ferbam spray treatments and the nabam spray treatments. Even though trees sprayed with fixed copper produced fruits with lower soluble solids content than those sprayed with ferbam or with nabam, the differences in soluble solids content of fruits from different orchards and In different seasons were as great or greater than the differences resulting from the use of spray materials® Fixed copper sprays had a greater unfavorable influence on number of fruits per grains and a more favorable influence on soluble solids content of fruits when used on trees of low vigor than did sprays of ferbam or nabam* Changing soil management from sod to clean cultivation resulted in a significant decrease in soluble solids content and increase in weight of harvested fruit which was related to increased vigor of the trees® TABLE OP CONTENTS Page ................................. 1 REVIEW OP LITERATURE................................... 3 INTRODUCTION. . . . . MATERIALS AND M E T H O D S ....................................16 Soil Management. • • • • • • . • • • . . . ........ 16 Design of Experimental Spray Blocks. . . . . • • • • 18 Spray Application. 18 Sampling Procedure * • * • • • • • • • • • • . • . . 20 Procedure for Gross Measurements and Chemical Determinations • • • • ........ . . • • • • • • . 21 R E S U L T S .................................................. 23 Effect of Time of Harvest on Physical and Chemical Changes of Sour Cherry Fruits. • « . • • • • • • • Number of fruits per i|_54- grams* 23 23 Size of fruits. . . * . . • • * • • • ............. 25 Firmness of flesh 29 Soluble solids content. • • • . • • • • • • • . « 29 Total solids content. • • • • • • • • • • . . • • 31 Total sugar content . • • • • • • • • • • • • . • 35 Specific gravity of fruits. 39 Effect of Organic versus Inorganic Spray Materials on Physical and Chemical Changes of Sour Cherry Fruits • • • • • • • . . « . .................... Number of fruits per I4.5 I+ grams. 1+2 .......... 1+2 Soluble solids content. • • • • » .............. 1+7 Individual Orchards. Orchard A (Morrison orchard S ) . . . . 52 . . . . « • 52 Number of fruits per 1+51+ grams. . . o . . . . . 52 TABLE OP CONTENTS CONT. Page Soluble Orchard B solids content. • « • « . . 55 (Morrison orchard C ) . . . . . . . . . * 57 Number of fruits per 1+51+ grams# Soluble Orchard C . . . . . . o • 57 solids content. • . . ............... 59 (McLachlan orchard) . • • • • • • • • • 61 Number of fruits per 1+51+ grams. . . • • • • • . 61 Soluble solids content. . . » • • » 63 • . . • • o Orchard D (Stokeley orchard)• 65 Number of fruits per 1+51+ grams® • Soluble solids content. Orchard E (Pox and Sons o 65 . . . « • • r c h a r d 67 ) Number of fruits per 1+51+ grams. • • • • . • • . 69 Soluble solids content. . « • • • . • • « . 72 .. Combined Results from Five Commercial Orchards • . • Number of 75 fruits per 1+51+ grams. 75 Effects of spray chemicals. • • . • . • • • • « 75 Effects of orchard management 79 Effects of variations in seasons. . . . o . . . 79 Soluble solids content. 8l Effects of spray chemicals. » • • • • » • • . • 8l Effects of orchard management . . . . . . . . . 81+ Effects of seasonal variation . . . o . . . « . 81+ DISCUSSION SUMMARY 69 . 86 ............................................ 95 LITERATURE CITED............ 99 INTRODUCTION It has been the belief of many food processors that the use of certain of the newly Introduced organic fungi­ cides on sour cherries (Primus cerasus L.) for control of leaf spot (Coccomyces hiemails H.) has reduced the quality of the processed product and has caused the processed cherries to be low in drained weight. This reasoning has been based on reports (1 4 , 20, 21, 22, 2 3 * 3 2 ) that the use of organic fungicides reduced the soluble solids con­ tent of the harvested fruit. Also a report by Lewis and Groves (23) included the statement that the increase in the solids content of harvested fruit from 11+ to 1 8 percent may Increase the number of No* 10 cans obtained In process­ ing 1,000,000 pounds of raw cherries by 11,500 cans. It Is common knowledge that cherries received by processing plants come from orchards of varying ages and vigor. Kenworthy and Mitchell (19) found that vigor of trees had a pronounced effect on the soluble solids content of the harvested fruit. There was some indication (21) also that sour cherries harvested at the time fruits may be picked without pulling the pits, are lower in soluble solids content than If allowed to hang until the end of the harvesting period. In Michigan the duration of harvest is approximately three weeks. 2 Th© available published information on sour cherries still leaves many questions yet unanswered* Thus the following study was undertaken to determine: (1) The effects of certain fungicidal chemicals on the soluble solids con­ tent and size of sour cherry fruits when used on trees varying in vigor and when used on trees growing under different soil conditions in more than one cherry producing area of Michigan; (2) The relation of time of harvest on the soluble solids content and size of cherry fruits; (3) Whether or not there is a direct correlation between the increase in soluble solids content, total solids content and sugar content of cherry fruits as the harvesting season progressed* REVTEW OP LITERATURE For many years the copper fungicides, Bordeaux and fixed copper, were the principal chemicals used to control leaf spot (Coccomyces hiemails H.) on sour cherry trees (Primus cerasus L*) (17)• However, after the introduction of ferbam (ferric dimethyl dithiocarbamate) in 1939 other new chemicals were found which had acceptable fungicidal properties with less unfavorable physiological effects on the tree* Some of these materials have received widespread use In the cherry growing industry* Numerous references are available on the physiological effects of Bordeaux and fixed copper on sour cherry trees when these chemicals are used to control leaf spot. The information on the physiological effects of certain organic fungicides, when used In place of the copper materials, is less numerous* The first report that physiological changes of sour cherry fruits are related to spray chemicals was made in 1923 by Button and Wells (8)* They reported a noticeable reduction in size of fruits from Montmorency trees and from English Morello trees sprayed with Bordeaux* In fact, the cherries were so much smaller than the fruits from trees of other spray treatments that the pickers objected to picking them* Further work by Dutton and Wells (8) showed the comparative sizes of Montmorency cherry fruits from different spray plots as follows: unsprayed check 100, dusted with sulfur 95* sprayed with lime-sulfur 85 sprayed with Bordeaux 63# The fruit from the unsprayed treatment was given the arbitrary figure of 100 for purposes of comparison* There was no defoliation from leaf spot of any trees before harvest* According to Blodgett and Magie (2) and Keitt and Clayton (18) Bordeaux was a more efficient spray material for leaf spot control than lime-sulfur* Blodgett and Magie (2) found very little differences in size of fruit from plots sprayed continuously with Bordeaux and with lime-sulfur* ll|., 18)* This does not agree with other findings (6 , Mills, Lewis and Adams (30) reported a significant negative correlation between spray injury and size of fruit and positive correlation between size of fruit and total yield* Cation and Rasmussen (6 ) found that trees thoroughly and timely sprayed with lime-sulfur in an orchard where primary leaf-spot infection was slight produced greater yields of larger sized fruits than trees sprayed with highcalcium-lime Bordeaux* Trees sprayed with fixed copper were comparable with those sprayed with lime-sulfur in yields and in size of fruit* Bordeaux caused dwarfing of fruit in years of low rainfall* In earlier studies Rasmussen (38) stated that the size of cherry fruits appeared to be inversely proportional to the concentration of the Bordeaux mixture* However, Miller (28) found no 5 relation between size, color, and sugar content of sour cherry fruit and the concentration of the copper in the spray# Langer and Fisher (20) and Fisher (12) working with ferbam and with fixed copper found in one orchard that the sour cherries sprayed with fixed copper were no smaller than those receiving ferbam# Xn the second orchard, how­ ever, the ferbam treatment increased the size of the fruit# Even when a heavy spring application of ammonium nitrate was used, the fruits of the trees receiving the ferbam treatment were larger than those from trees of the fixed copper treatment# Xn this study, the size of cherries was measured by volume and weight# Work in West Virginia and Pennsylvania as reported by Lewis and Groves (21) and Lewis (2 J4.) indicated that the use of ferbam resulted in cherries of smaller size than did treatments of either fixed copper or nabam plus monohydrate zinc sulfate# The suggested reason for this was that ferbam failed to control leaf spot# Moore and Keitt in Wisconsin (3 2 ) found both ferbam and nabam plus monohydrate zinc sulfate as favorable as fixed copper for the control of leaf spot on Montmorency cherries and at the same time the use of these two organic chemicals increased the size of fruit over those from the trees sprayed with fixed copper# Groves, Miller and Taylor (lij.) in 19i+0 and 19ip. found that Bordeaux significantly reduced the size of fruit in their investigations in Virginia, Pennsylvania, and West 6 Virginia when compared with cherries from trees sprayed with sulfur compounds, fixed copper and Crag 3^+1 (2-heptadeeylglyoxalidine)« In 19i+0 Bordeaux significantly reduced the size of fruit as compared with fixed copper and fixed copper reduced the size of fruit as compared to the unsprayed check* Xn 191+1 Bordeaux significantly reduced the size of fruit below that of the check, the fixed copper treatments and the organic treatments* The differences between the fruit from the fixed copper and organic spray treatments were minor. The reduction in size of cherry fruits from trees sprayed with alkaline sprays which contain copper such as Bordeaux has been acknowledged by many workers (8 , 10, 11, 31, 3&> i+2)* The first reports of reductions in size of fruits owing to alkaline sprays were by Fisher (11) in work on sweet cherries, and by Dutton and Wells (8 ) in their studies of sour cherries* Fisher (11) stated that in each case reduction in size of the ripe cherries (sweet) was in proportion to the spray* the> amount of alkaline material in And, a wash of lime and lamp-black resulted In no greater dwarfing than occurred from the application of lime alone, Indicating that the reduction in illumination was not the cause of smaller fruit* Dutton and Wells (8 ) found also that a hydrated lime spray reduced the size of sour cherries* Fisher (11) stated further "The results Indicated that dwarfing by alkaline sprays is brought about through excessive transpiration or water loss occasioned 7 by the destruction of the wax bloom*" Verner (if2) con­ cluded from his observations that calcium was the effective constituent of Bordeaux mixture in its action on cracking of sweet cherries and that probably only the calcium in solution was effective* He suggested that the presence of calcium in the spray modified the degree of permeability of the sweet cherry fruit skin and the plasticity of the peripheral tissues, reducing the tendency for cracking from excessive absorption of water. The possibility of internal effects of lime on physical changes of the fruit of Bing cherry trees was investigated by Bullock (i^.)* The calcium salts were inserted into the trunk of the tree beyond the cambium* He found a tendency toward a reduction in fruit size when the cation, calcium, was injected as a solid in a gelatin capsule; but, when the calcium was injected in liquid form, there was no effect on fruit size* The effect of calcium on the physiological processes of sour cherry fruits was investigated also by comparing high-calcium and high-magnesium Bordeaux mixtures. Ras­ mussen (3^), Dutton and Farish (10), and Moore (31) have shown that injury was less when the high-magnesium Bordeaux was used* Rasmussen (36) suggested that the copper in the high-magnesium lime Bordeaux is apparently held in a less soluble form and thus it was less toxic to foliage and not as readily absorbed as the copper in the high-calcium lime Bordeaux. The toxicity of lime may be associated with its capacity to make copper less soluble* 8 Copper injury has been reported on crops other than sour cherries* Suit (39) observed that Concord grapes were injured by sprays containing neutral copper compounds which had a copper content equal to that of* ij.-lj.-100 Bordeaux mixture. The injury was characterized by reduced vine growth, by smaller yellowish-green leaves and by reduced yield* He found that the yield obtained the year following the spray applications was reduced even more, although a copper fungicide was not used. The second year following the injury by copper compounds, the yield from the previously injured vines had increased so that it was equal to that of vines which had not been injured by copper. cated that the spray material caused the injury. This indi­ Obser­ vations of the cane indicated that fixed coppers at a copper concentration equal to ij.-l4.-l00 Bordeaux caused severe reduction in growth but the addition of lime appeared to alleviate the injury. Suit (38) reported further that in other experiments, plants sprayed with Bordeaux were stunted, leaves were deformed and yields were reduced. This did not occur when Bordeaux substitutes were use do Lewis and Groves (23) and Taylor (I4.O) found that during many seasons cherry trees sprayed with copper base fungicides were defoliated almost as extensively as the trees heavily infected with leaf spot# They also described a common type of Bordeaux injury to be yellowing and dropping of leaves, similar to drought injury and a leaf spot almost identical with that caused by Coccomyces hiemails H# However, the fungus leaf spot was identified 9 readily by the presence of spore masses on the lower surface of the spot. Dutton and Wells (9) have reported that drought injury of sour cherry trees sprayed with copper compounds was increased during prolonged, dry, hot periods which they feel indicated that copper may accentuate the rate of transpiration of the leaves* (31) and Rasmussen (37)* This was verified by Moore fn contrast to this, Daines (7) observed that during wet periods certain copper fungicides gave considerable injury especially where lime was omitted. Lewis and Groves (23) reported increased injury to cherry leaves during either excessively wet or dry periods. Numerous workers have acknowledged generally that fruits from trees sprayed with Bordeaux or other forms of copper contain a higher solids concentration than fruits sprayed with fulfur compounds and organic materials (1 , 2 , 3* 6 , ilf, 19> 2 0 , 2 1 , 23# 21*., 3 0 , 3&* U4) * and that an increase in solids concentration was usually related to a decrease in size of fruit. However, this relationship of size of fruit to solids content was not always true. This was shown by data from reports of Cation and Rasmussen (6 ), Lewis and Groves (22, 23) and Groves, Miller and Taylor (1i± ) 0 Langer and Fisher (20) and Fisher (12) found that fruits from trees sprayed with ferbam contained a higher percentage of soluble solids than fruits sprayed with fixed copper. However, results with these same materials were less conclusive in the work by Groves, Miller, and Taylor (li|.) <» 10 Studies reported by Lewis and Groves (21) and Langer and Fisher (20) indicated that dwarfing of fruit concentrated the soluble solids in less juice thus increasing the per­ centage of soluble solids in the small fruits. However, Lewis and Groves (23) stated that the low soluble solids content of fruits from trees sprayed with Crag 3^4-1 appeared to be too low to be accounted for by the increased size of the fruit* Xt has been suggested by Rasmussen (37) that the increased solids and sugar content of cherries from trees sprayed with the higher concentrations of Bordeaux may be due to the increased rate of transpiration of the leaves thus reducing the water content of the fruit and increasing the concentration of solids and sugar in the fruit* The decrease in water content of cherry fruits through trans­ piration was pointed out also by McMunn (26)* He stated that several investigators have shown that cherry fruits may have marked diurnal changes in volume, even though there is ample moisture in the soil. Such diurnal fluc­ tuations are brought about, he explained, by the trans­ piring leaves creating a deficit of water which cannot be supplied by the root system even though moisture is avail­ able* He also reported that a study of weather records for ten years indicated that low humidity was probably the most influential factor in creating deficits of water. Rasmussen (3 7 ) adds that the low solids and sugar content of fruits from cherry trees sprayed with lime-sulfur may be attributed 11 to a reduced photosynthetic activity of leaves. Murphy (33) found that lime-sulfur, 6-8-100 Bordeaux, and Coposil (fixed copper) reduced the amount of photosynthate in the > rv- cherry leaves, indicating a reduction in the rate of photo­ synthesis. However, Laustalot (25) working with mature pecan leaves found no appreciable effects on either photo­ synthesis or transpiration with as many as three sprays of 8-8-100 Bordeaux or lead arsenate even though the leaves receiving these sprays were so well covered that the green color was hardly visible® Groves, Miller, and Taylor (1if), working with organic spray chemicals, suggested the possibility of arsenical materials increasing the soluble solids content of fruits® Their results showed an increase in soluble solids where lead arsenate was included in the spray schedule. Relating to this, Miller, Bassett, and Yothers (29) * working with citrus, found that arsenical compounds hastened the maturity of oranges, although the effect was more one of altering the ratio between solids and acid content rather than an absolute increase in sugar content. However, Juritz (15) found that lead arsenate sprays reduced the sucrose content in orange juice below that of unsprayed fruit, from if.!^ percent in the unsprayed fruit to 3 * 6 5 percent in lightly sprayed fruit, and to 1 . 1 2 percent in heavily sprayed fruit* The work of Kenworthy and Mitchell (19) indicated that soil management practices such as sods, cultivation, mulches and fertilizers as well as climate and seasons may have a 12 significant effect upon the soluble solids content of Montmorency cherries* They report that a significant negative correlation of leaf nitrogen with the soluble solids content of the fruit was found in 194-9* suggesting a possible correlation of tree vigor with soluble solids as indicated by Langer and Fisher (2 0 )* It has been suggested by Johnsen, Kenworthy, and Mitchell (16) that the relation of soluble solids to 1b af nitrogen and tree vigor might be associated with Internal leaf structure* According to Meyer and Anderson (27)* if the supply of nitrogen compounds to any growing meristem is abundant relative to the supply of carbohydrates, a large quantity of protoplasm will be synthesized relative to the amount of cell wall material formed* Thus the resulting cells will usually be large, thin-walled, and well stocked with protoplasm« Pickett and Birkeland (35) have shown that the extent of the internally exposed cell walls in the apple leaves was closely associated with their photo­ synthetic activity as measured by the Increase In dry weight of the tree per unit of leaf area 0 Work by Johnsen, Kenworthy, and Mitchell (16) showed that spray treatments had a very marked effect upon the depths of the palisade mesophyll of cherry leaves. Leaves sprayed with fixed copper had a thinner palisade layer than leaves sprayed with ferbam. Leaves sprayed with liquid lime-sulfur had a thicker palisade layer than the leaves receiving either fixed copper or ferbam. They found also that Including parathion with the fungicide resulted in 13 greater palisade depth than the use of either benzene hexachloride or lead arsenate. As a result of this study they felt that the sprays which result in the greatest depth of palisade mesophyll of the leaves should be favorable also to the best vegetative growth and the highest yields* Caldwell (5) reported on some of the physical and chemical changes normally occurring in cherry fruits from the time the fruits were six to eight millimeters in length and four to six millimeters in diameter until fully ripe* He found, that for the Montmorency variety, the most rapid increase in acidity occurred between June 5 and 18 and during this period the solids in the fruit increased only 6 * 5 percent while the water increased 2lj.8 percent* In the very young fruits there was an initial stage of rather high moisture content, followed by a very abrupt decline* He reports nAs the fruit whitens, water content again rises rapidly to a maximum, then declines as the fruit becomes fully ripe . 11 In all the varieties of cherries there was a rapid hydration of the tissues accompanying the period of most rapid increase in acid concentration* Tukey (Ip.) found three distinct stages in the develop­ ment of the sour cherry fruit; namely, a period of rapid increase in size following fertilization (Stage I), a period of delayed increase in size during mid-season (Stage IT), and a second period of rapid increase in size to fruit ripening (Stage H T ) « In Montmorency cherries the duration of each stage was as follows: 22 days for Stage I, 12 days li+ for Stag© IX, 23 days for Stage III, making a total of 57 days from full bloom to fruit ripening* The volume as measured by water displacement showed strikingly the rapid fruit development during "Stage I" and "Stage III"* During "Stage I" Montmorency fruits increased in volume nearly 3 0 , 0 0 0 percent and during the 2 5 days proceeding ripening increased 296 percent. The mean diameter of fruits, representing the length diameter, suture diameter, and check diameter was proportional throughout fruit development to the "volume diameter", computed by deter­ mining the diameter of a sphere having a volume equal to the volume of water actually displaced by the fruit. He found that the cheek diameter measurement reflected the rate of growth in volume of the cherry fruit as the season progressed. Little to no studies have been made on the changes that take place in the cherry fruits during the prolonged period of harvest* The only work of this nature that has come to the attention of the author was that of Lewis and Groves (21) on the changes in soluble solids content of the fruit* They reported an Increase In soluble solids content of the fruit from June 23 to July 13, a period during which there was no appreciable rainfall* However, from July 13 to 2 1 , following a light rain, the soluble solids content remained fairly stable but decreased slightly In some Instances, The differences between treatments varied during the entire period (June 23 to July 23), with the 1? greatest differences occurring between July 13 and 23 when the cherries were fully ripe and had started to shrivel badly on the Bordeaux sprayed trees# The findings in this study did not agree with preliminary data secured in 1 9 4 3 * as the solids content of the cherries of different spray treatments did not reach a similar peak on different dates* MATERIALS AND METHODS The fruits for this investigation were obtained from a seven-year-old Montmorency planting of 64 trees growing on the Horticultural Farm, Michigan State College, East Lansing and from five commercial Montmorency cherry orchards located in the cherry growing areas of Michigan* Four of the commercial orchards consisted of large trees in good bearing vigor while the fifth orchard was made up of bearing eight- to ten-year-old trees which had been pro­ ducing £ 0 to 7 5 pounds of cherries for the past four years* Soil Management The five commercial orchards varied in soil management as follows: Orchard A (Morrison orchard, Acme) - Sod plus straw mulch In 1949; trashy cultivation in 1950 and 1951; and clean cultivation plus cover crop sown in August, 1952* All trees received spring applications of nitrogen and barnyard manure was broadcast in the orchard annually* The trees were in good bearing vigor* Orchard B (Morrison orchard, Acme) - Clean cultivation plus a cover crop sown In August* All trees received spring applications of nitrogen and barnyard manure 17 was broadcast in the orchard annually. The trees were in good bearing vigor# Orchard C (McLachlan orchard, Kewadin) - Trashy culti­ vation. The grass and weed cover was checked period­ ically by cultivation but was not incorporated into the soil. All trees received spring applications of nitrogen* The trees were in good bearing vigor in 19*4-9 and 1950. However the occurrence of winter injury in 1 9 5 0 and 1 9 5 1 reduced the vigor of the trees. Orchard D (Stokeley orchard, Hart) - Glean cultivation plus a cover crop sown in August. spring applications of nitrogen. All trees received These trees were approximately six years old at the beginning of this study and were in good vigorous condition. Orchard E (Pox and Sons, Shelby) - Trashy cultivation. The grass and weed cover was checked periodically by light cultivation. All trees received heavy spring applications of nitrogen annually. In 19*4-9 these trees were low in vigor, however, through the contin­ uance of heavy fertilizer applications, the vigor was increased greatly so that in 1 9 5 1 and 1 9 5 2 the trees were in a high state of vigor. The cherry orchard on the Michigan State College Horti­ culture Farm at East Lansing was maintained in sod plus straw mulch. Fertilizer was not used in this block the two years this study was in progress in hopes that the perform­ ance of the trees would reflect the physiological effect 19 of the spray chemicals which were used for pest control. The trees, generally, were low in vigor because of the omission of nitrogen fertilizer and the competing sod. Design of Experimental Spray Blocks Three spray blocks, each containing three rows of trees, were used in each commercial orchard. Two of the blocks received organic fungicides and the third block (control) was sprayed with fixed copper. Five single tree replicates were selected for uniformity of size and vigor from the center row of trees of each plot. Replication of location was accomplished by duplicating the treatments in five orchards in various locations in the cherry pro­ ducing areas of the State, For the spray studies on cherries in the Michigan State College Orchard on the Horticulture Farm, East Lansing, groups of two trees were selected randomly, each treatment containing four groups of two trees making eight trees per treatment. Spray Application The five commercial orchards received five pre-harvest spray applications and one post-harvest spray application during each of the four years. The sprays were applied with automatic equipment by the grower at the time he sprayed the remaining portions of his orchard. The pre- 19 harvest spray treatments and the amounts used per 1 0 0 gallons In each of the five commercial orchards were as follows: a, Ferbam (ferric dimethyl dithiocarbamate) lj- pounds b* Fixed copper - 0*75 of a pound of metallic copper plus 3 pounds of hydrated lime c* Nabam (disodium ethylene bisdithiocarbamate) on© quart plus ^ pound of monohydrate zinc sulfate d. Lead arsenate - 2 pounds in all pre-harvest sprays In three of the four years (1950 through 1952) Orchards A and B received added applications of parathion at the time of the first cover to control case-bearer (Coleophora malivorella Riley)* Parathion was used in Orchard C in 1 9 5 2 in place of lead arsenate at petal fall and first cover to control the Mineola moth (Mineola scituilla Hulst)* A post-harvest application of fixed copper, using 0 * 7 5 ofa pound of metallic standard practice each copper per 1 0 0 gallons, was year in each of the five commercial orchards • Five pre-harvest sprays and one post-harvest spray each season was used also in the Michigan State College Horticulture Farm Orchard. The pre-harvest spray treat­ ments and the amounts used per 1 0 0 gallons were as follows: 1* Fixed copper - 0.75 of a pound of metallic copper plus 3 pounds of hydrated lime and 2 pounds of lead arsenate 2* Fixed copper - 0.75 of a pound of metallic copper 20 plus 3 pounds of hydrated lime and 1 pound of 15 percent wettable parathion 3* Fermate - 1*5 pounds plus 1 pound of parathion k* Ferbam (ferric dimethyl dithiocarbamate) - 1.5 pounds plus 2 pounds of lead arsenate The post-harvest spray on all plots consisted of 0.75 of a pound of metallic copper plus three pounds of hydrated lime * Sampling procedure Samples of fruit were collected from the five commer­ cial orchards just a few hours before the growers harvested the cherries in that particular orchard. Approximately 7 0 0 grams of cherries from clusters of three or more fruits were picked at random from one side of each of the large trees in Orchards A, B, C and E and from the entire tree in Orchard D. The samples were taken from the same portion of the tree each year* In the spray plots at Michigan State College Horti­ cultural Farm, East Lansing, samples of fruits were collected approximately 1 0 days after the beginning of commercial harvest. Each sample included approximately 700 grams of cherries which were taken at random from the entire tree 0 Only cherries from clusters of three or more fruits were harvested at each time of sampling* For detailed studies to determine the effects of time of harvest on chemical composition and size of cherry fruits, 21 four trees of uniform size and crop load were selected in the spray plots at the Michigan State College Hortii cultural Farm. Fruits were harvested twice weekly, beginning as soon as the fruits could be picked without the pit being removed from the fruit and continued until the fruits started to shrivel on the trees* Here again samplings were made from the entire tree and each sample included approximately 7 0 0 grams of cherries taken from clusters of three or more fruits* Procedure for Cross Measurement and Chemical Determinations Gross measurements and chemical determinations were made on the harvested fruit as follows: a* Weight of fruits - the number of fruits required to make 4 5 4 grams (one pound)* b* Size of fruits - the average transverse diameter in millimeters of 2 0 fruits, an imaginary line perpendicular to the plane formed by the dorsal and ventral sutures, Tukey (IpL)* c* Soluble solids - determined from the juice of 20 fruits using an Abbe* refractometer* d* Total solids - average of three samples of five fruits ee.ch, including the pits and flesh, using the procedure as described by A. 0. A. C. (34)* The pits were cracked to reduce drying time* e* Firmness of flesh - percent compression of the flesh of 2 0 cherries using the method described by Whittenberger and Marshall (43)• 22 f*o Total sugars - determined by Munson-Walker General Method (25) as described by A* 0 # A. C. (3I|-)® g« Specific gravity - calculated from the volume of water displaced by the fruit* RESULTS Effect of Time of Harvest on Physical and Chemical Changes of Sour Cherry Fruits The progressive physical and chemical changes taking place in sour cherry fruits harvested from the Michigan State College Horticulture Farm orchard, East Lansing, during the commercial harvesting period of 1 9 5 1 and 1 9 5 2 are given in Tables 1 through 12. Number of fruits per grams Xn 1 9 5 2 the average number of fruits per grams decreased significantly during the first three days of harvest, from 162 fruits per i|_5i+- grams on June 30 to 152 fruits on July 3> then remained fairly uniform through July II4. (Table 1). However, on July 1?, the number of fruits per i+54 grams had decreased significantly, from 1 5 6 fruits on July lij. to ll\. 6 fruits on July 17 and continued to a low of 139 fruits on July 21, after which time the number had increased again to 151 fruits on July 2Ij. and continued to be the same on July 28# This pronounced decrease in number of fruits per I4S k - grams may be explained in part by a continued period of wet weather from July II4. through July 23 giving a total of 1.93 inches of rain for this 1 0 -day span* 2k TABLE 1 THE EFFECT OF TIME OF HARVEST OH THE HUMBER OF SOUR CHERRY FRUITS PER k S k GRAMS (East Lansing, 1952) Tree June 30 3 7 Dates of harvest July 10 17 14 21 21|- 28 1 155 1/+8 l5l 114-6 15?- 137 135 114-2 II4.2 2 1 6 I4. 156 155 153 163 150 114-3 153 155 3 160 1 U.8 i5i 142 114-2 11a 128 114-0 II4.O ' 170 158 161 161 167 156 114-9 16 8 165 Average 162 152 155 151 156 II4.6 139 l5l 151 L •S «D • - 6} k - 10 Not©: 1*93 Inches of rain was received between July llj. and 23 o 25 Size of fruits Linear measurements of the greatest transverse diameter of the cherry fruits, called cheek diameter by Tukey (ill), reflected no apparent increase in the average size of the fruit in 1 9 5 1 or in 1 9 5 2 after the first three days of commercial harvest, from June 30 to July 3 (Table 2). Tukey (Ul), comparing various methods of determining increase in size of fruit, found that the cheek diameter of the Montmorency cherry fruits increased but slightly, only Ool of a millimeter, the first seven days of commercial harvest« He found an increase of only 0*2 of a millimeter for the volume diameter computed from the actual volume of water displaced by the cherry fruits, and an increase of only 0 . 1 of a millimeter for the mean diameter which was a computed measurement, an average of the suture diameter, cheek diameter, and the length of the cherry fruit. Accord­ ingly, as the results of these different methods of measuring increase in size of Montmorency cherry fruits varied only slightly, it seems safe to assume that the cheek (trans­ verse diameter) may reflect any appreciable change in size of fruit. The average increase in transverse diameter of fruits was O.ii of a millimeter for the first five days of harvest in 1951, from 1 8 . 7 to 19*1 millimeters and 0 . 6 of a milli­ meter during the first three days of harvest in 1 9 5 2 , from 18.2 to 18.8 millimeters (Table 2). Although the trans­ verse diameter fluctuated slightly during the entire harvest- 26 TABLE 2 EFFECT OF TIME OF HARVEST ON THE TRANSVERSE DIAMETER (IN MILLIMETERS) OF SOUR CHERRY FRUITS (East Lansing) Season Tree 1951 Average 2 6 19 1 18.5 18.9 18 #6 19.2 18.5 19.0 18.5 2 1 7 .8 18.3 1 9 .0 17.7 1 8 .2 1 8 .6 1 8 .6 3 19.5 2 0 .0 19.6 19.1+ 19.1 19.5 19.0 k 1 8 .8 19.2 19.2 18.9 1 8 .8 19.1 1 8 .6 18.7 19.1 19.1 1 8 .8 18.7 19.1 18.7 17 21 5% - 0.5 June 19?2 Augus t 14 Average L.S.D. Dates of harvest July 26 30 23 July 30 3 7 10 X 18.3 1 9 .0 19.0 18.9 1 8 .1+ 19.5 19.1 2 18.3 1 8 .6 18.9 1 9 .2 1 9 .0 1 8 .6 18.9 3 18.3 19.4 18.9 19.1+ 1 9 .6 19.3 19.7 4 1 8 .0 1 8 .1 1 8 .6 1 8 .$ 1 8 .2 18.7 19.0 1 8 .2 1 8 .8 18.9 1 9 .0 1 8 .8 1 9 .0 19.2 L.S.D. 5$ - 0.5; 1 % - 0.7 Ik 27 Ing period in 1 9 5 1 * none of the changes, increases or decreases, were significantly different from the average transverse diameter of 1 8 * 7 millimeters obtained at the first time of sampling, July lij.« Xn 1952 there was a sig­ nificant change in average transverse diameter on the second date of sampling after which time there were only slight fluctuations in size until July 21* On this date the fruits had increased 0 „1| of a millimeter, from 1 8 * 8 milli­ meters on July U 4. to 19*2 millimeters on July 21. Although this increase was not significant it may have been influenced by a rainy period which started on July llj. and continued through July 23 o The fluctuations of the average transverse diameter of cherry fruit in 1 9 5 2 , just described, were reflected also by the calculated "mean1* diameter of fruits selected randomly from the same picked sample (Table 3)* The average "mean” diameter of the fruits was consistently slightly less than the average transverse diameter, throughout the harvest season 0 The trends in average transverse diameter of 20 fruits from each sample were similar to those shown by the average number of fruits per I\S l± grams* However, the average trans­ verse diameter did not show the increase in fruit size on July 17 and 21, indicated by the significant decrease in number of fruits per grams on those dates. This could not be explained, unless the increase in transverse diameter per fruit was too small to be detected by the means used to 28 TABLE 3 RELATION OP TRANSVERSE DIAMETER AND MEAN DIAMETER (IN MILLIMETERS) OP SOUR CHERH5T FRUITS TO DIFFERENT DATES OF HARVEST (East Lansing) Dates of harvest July June 30 3 Average trans­ verse diameter 18 * 2 1 8 .8 Average mean diameter 1 7 .8 1 8 ,2 10 Ik 17 21 18.9 1 9 .0 1 8 .8 1 9 .0 19.2 1 8 .1 1 8 .3 1 8 .2 1 8 .6 18.9 7 29 make this measurement, or unless the changes in weight were the result of changes in density* Firmness of flesh A comparison of firmness of flesh as related to date of sampling is given in Table 4.. As shown by these data, fruit collected on July 26, 1951* were significantly less firm than fruits of July 14, and July 23* 1951# Similarly, fruits picked on July 10, 1952, were significantly less fiira (an increase in percent compression) than fruits of June 30 ancL July 3* 1952* The fruits became more firm after July 26, 1951* and after July II4., 1952. The rapid increase in firmness after July 26, 1951* was probably a result of the rapid loss of water by the fruit. The firmness of flesh of Cherry fruits appeared to have very little relation to average diameter of fruit (Table 2). This was not entirely in agreement with the report of Whittenberger and Marshall (ij-3)* who found the larger cherries slightly firmer than the smaller ones with the method of evaluation of firmness used in this study. A possible explanation for that difference is that their findings were based on measurements of cherries selected for uniformity of diameter and maturity while the findings reported herein are measurements of cherries selected at random from tree-run fruits. Soluble solids content The average soluble solids content of the cherry fruits 30 x0 9 cA CM O' • C^rH CM « cA CM A• i—1 CM LA o rH CM Ah CM CM O o CM CM xO « O CM LA • cA CM xO • CM CM CM 0 CM CM pH CM LA • LA CM C o LA CM CO • Ah CM CO • Ah CM CM • LA CM Ai—1 xO CM Ah • So CM O' • LA CM O • LA CM CO • LA CM CD • LA CM J5* ' H A * 0 rH CA C\J 1A • CA CM O • Ah CM CM • rA CM CA • CA CM •LA • CA CM O i—1 CM • Ah CM A— o LA CM GO • CM CM CO • CA CM rH 0 CO a cA CM "LA a xO CM CA •LA • 1—1 CM oa -p GO 3 O' • •LA 1—1 A— 0 xO i—1 rH O' 0 0 O' 1—* O' rH O' 0 A1—1 CA o a rH 9 A1—1 xO 0 O' 1—I A— 9 O' 1—1 Ah 9 CO 1—1 CA o O' i—1 CM 0 1-- 1 CM CO o O' 1—1 'LA 9 O CM CM o O 0 Ah * rH CM CM GO 0 O' 1—i CO 0 CM CM xO 0 xO • O' 1—1 o w COMPRESSION 3 <*J THE INFLUENCE OF TIME OF HARVEST ON FIRMNESS OF FLESH (PERCENT IN MILLIMETERS) OF SOUR CHERRY FRUITS o CA rH to *“3 0 o xO o GO rH Ah 0 CM o O' 0 CO 1—1 LA 9 A- CM 0 o o CM 0 o CM o •i—i to O' -p pH to cti W pH 0 CM CM o CM CM 1--1 CM CM LA o rH CM •LA 0 CA CM I— 0 A~ rH CA o CO rH O 0 A1—1 •LA o CO rH A- -=t CA t> o to ai < * p CM LA O' rH • Q • CO • p 31 increased significantly as the harvest season progressed in 195l (Table 5)• However, in 1952 the soluble solids content increased significantly only during the first two weeks of harvest after which time there was no significant change (Table 5 and Figure I)* Comparing the soluble solids content of the fruits of individual trees at the beginning of har­ vest in 1 9 5 1 and 1 9 5 2 , the variation was considerable, from 15.1 to 17*5 percent in 1951 and from 1 2 ©9 to li]-®5 percent in 1952* A similar variation between trees was found in every commercial orchard. In both years, 1951 and 1952, trees with fruits high in soluble solids at the beginning of harvest continued to produce fruits high in soluble solids at the end of the harvest period, while those trees producing fruits low in soluble solids at the beginning of harvest continued to produce fruit low in soluble solids by comparison when the experiment ended. These data indicate that time of picking during the harvesting period will influence the soluble solids content of the fruit© Total solids content The increase in the average total solids of the har­ vested fruit followed a trend very similar to that described for soluble solids during both 1 9 5 1 and 1 9 5 2 harvest seasons (Table 6 ). Throughout the entire periods of harvest in 195l and 1 9 5 2 , there continued to be only a slight variation between the total solids content of the fruits from trees 1, 2, and h © But, the total solids content of the fruits from tree 3 was always the lowest on each date of sampling© 32 O vO rH • rH OJ CO • p- CO o O OJ CO • CO rH co OJ o OJ o - in • • CO o i—1 rH co • o OJ in • co i—i -d * OJ r— o o OJ co • co rH CO • vO -d * * CO rH OJ o CO 1 —1 vO * rH o rH OJ 1 —1 CO o O OJ 1 —1 co CO • CO rH rH CO <► * co n rH rH rH 1 —1 O • CO 1 —I in • vO rH OJ CO rH O O CO rH CO to - CO 0 • CO in 1 —i rH CO • CO rH vO O! • CO rH OJ • CO O O- co 0 CO 1 —1 CO • GO rH -p 03 2 bC d Sh OS S in v£> 43 co O pq O 1—> & CO ft; 00 0 -P cd Q Q pq 1—iW o O fd co t=> pq o I d CQ dl co Erl t-qo Ph o CO Eh 1 —1 bO OJ 1 —1 CO 0 0 1 —1 * 0 O- 0 • vO rH • CO rH CO o CO rH O vO • PiH CO • CO rH -d * 1 —1 O * CO rH 0 0 0 00 vO CO —1 1—1 1 —i 1 CO rH vO • to ­ rn O 1 —1 CO • vO rH CO O (—1 • 0 • p— m O— 1 —1 rH 1 —1 vO H O OJ 01 —1 >> r—i d 0— CO * • CO CO rH 1 —1 1 —1 iH 1 —1 03 N i—i d O £ *H W d 1 —1 0 co OJ i—i « • co O 1—1 OJ • vO i—1 co co • « p— CO rH I—1 CO o in iH O co i—i .-d pH OJ a v£> iH i—1 « in rH .-d* « in rH aJ t-q • P— iH -p OQ aj pq in a C— iH o o v£> i—1 p- o S Eh 0 CO 00 P=J m CO ■ \D 1 —1 0 O * v£> «H vO 1 —1 rH vC « ndiH O CO m in OJ - d 1 —1 rH rH 0 9 0 0 0 n 0 vO • in t—1 OJ « -d * rH co a rH w 0 o d d ■n £ pH O rH • CO 1 —1 m 0 _d* rH CO O • OJ -d rH rH 0 n£) • CO 1 —1 • • 00• p i OJ in CO rH • Q • CO • t~q 33 Percent 20 19 15 17 E 3 Perbom llllJ Copper E 3 Copper I . 1Ferbam + + + + lead arsenate lead arsenate parathion parathion s' s' s' 16 15 14 13 12 s' June 30, 1952 July 14, 19 XI July 28, 1952 Soluble solids Percent 26 25 24 23 22 21 20 19 18 1 June 30, 1952 July 14, 1952 July 28, 1952 Total solids 13 Peroent 12 11 10 July 34, 1952 July 28, 1952 Total sugar Figure I* The effects o f time of harvest, as related to spray treatment, on the soluble solids, total solids and total sugar content of sour cherry fruits in 1952 (East Lansing)* -d " - d vO CA o 0 r— . OJ OJ 00 vO rH • ■LA CM ca vO • LA OJ 00 o • vD OJ rH CO • rH CO OJ O • vO AJ CA CO • -d CM CA _d • ■LA OJ O O cA o v£> • cA 00 i—1 CO O CA o CM OJ co CA • CA CM vD 00 O CO • -d OJ T-A vO • vO OJ sO i—1 • i—1 C\J CA LA © CA CM CA O • -d * CO rH CO o CA 00 rH CA o CO OJ OJ • o 00 OO rH © CM CM CA vO • CM CM sO i—! • co OJ 1A CO o CA OJ o O' © CO rH C— cA © rH CM CO A© o OJ LA OJ o O OJ vO CO -d * o • m OJ rH o CM OJ OJ CO Q O OJ •p rH O • la X> CM -d * OJ • -d CM d* CM vO vO • -d * OJ CM TO S) 2 OJ CO pq (d Ph Ph o Eh is; pq o fd pq Ph •p 0Q © > Eh SE5 CO pq Eh Eh h IS p o « o pH TO 0 CO K pq« h a p m sO pq p 1 o o to sal Eh CO O Eh Ph is O O'-' hs i—1 S* ^T) CO OJ • rH CM ArH l>» CM rH o -d CM O OJ • cA CM la * i—l CM co CM o vO CM CA A* CA CM d © -d CM CM OJ • i—i CM AC— • LA OJ O CO o CA CM oo o o d CM CA CA • O CM d CA • CA CM cA rH • cA OJ -3r LA OJ CO rH • d CM Ai—1 * cA CM la d o CA CM d 0 rH CM •“3 -d" i—1 sO OJ a -d 00 CA d • d cM vO d OJ CO • • r—1 d CM 00 OJ vO o CA CM Ao « CM CM sO A« CM CM CA -d ' ALA • OJ CM i—1 A• i—1 CM vO rH • 1---1 CM d LA rH OJ • CA rH O v£> • i—1 CM ACA • O CM CA O • o CM Ad o CA rH vO O • CO rH GO d • o OJ -P of total O JH cd d nO O OJ © CA OJ cd w & P *0H 0 £ cd CA H O rH • CA H P -p co cd _d i—i pq Eh Eh W i—1 OJ O' rH A- 0 CA la CO t±s ga cd ^ ca EH pq i—t 1 0 0 CM CA _H- U EH © bO TO pq Ph EH ^ T O © > & O cd 0 CO rH ■feSL. rH LA O' OJ CA _d 'VS^ 0 bO cd P u • CO • P © LA P > ♦ «d P CM LA CA i—1 ^pits were included in the determination rH CA • -d * 00 v£> solids 3^ 35 This was true also for the soluble solids content (Table 5 and Figure I)* The average total solids and the total solids of the cherries of each of the four trees decreased on July 30* 1951* and on July 17, 1952. This may be explained in part by 1 027 inches of rain that fell on July 27* 1951, and by a 10-day rainy period from July lij- through July 23* 1952# Very little rain had fallen during the growing season previous to July 26 in 1951» However, approximately one inch of rain had fallen during the growing season previous to July lij. in 1952* The soil had been considered generally as very dry during the first part of both harvesting seasons 0 Even though the decrease in total solids of the fruits following the rain in both years (Table 6 ) was not signifi­ cant, it is recognized generally by processors that a larger "put-in” weight of cherries is required after a rainy period to obtain a certain drained weight than is required before the rain* The correlation of soluble solids content with total solids content of fruits as the harvest season progressed was highly significant in 1 9 5 1 (** = 0 *0 1 6 ) and in 1 9 5 2 (r = 0*966) (Figures XX and III)® Total sugar content Based on preliminary observations in 1951 of the increase in sugar content of cherry fruits as the period of harvest progressed (Table 7), a more detailed study of sugar content was mad© in 1952* The results of this study 36 29 27 Percent total solids 26 23 22 21 20 19 18 17 15 16 17 18 19 20 21 22 23 Percent soluble solids Figure I I • Regression of percent total solids on the percent soluble solids of sour cherry fruits. Fruits har­ vested twice weekly from four Mont­ morency cherry trees in 1951* (E = 0 . 6 7 5 X + 3 o 0 1 ) (r = 0 . 8 1 6 ) 37 Percent total solids 26 23 22 21 20 19 13 15 16 18 17 19 20 21 Percent soluble solids Figure III, Regression of percent total solids on the percent soluble solids of sour cherry fruits* Fruits harvested twice weekly from four Montmorency cherry trees in 1952* (E = loOOX - 5 d 3 ) (r = 0o966) 38 GO CM t»* rH CO (A • i—1 rH vO • O i—1 CO • OJ rH o d CM 0 CM i—1 i—1 OF TOTAL CM -p w © !> r— rH 0 cd THE EFFECT OF TIME OF HARVEST ON THE PERCENTAGE OF SOUR CHERRY FRUITS IN 19^2 rH i—1 C"• rH rH SUGAR 3 CNJ *“3 sO • CM rH CM • O • rH i—( 'LA • rH rH CO • t—1 rH d • rH l—1 lA • O O • O i—i o CO rH CA • CO * CM • rH rH i—1 rH O- CA rH i—1 rH CO • O i—1 rH 'LA • cO • i—1 r—1 CO CO fc d • O • CM • c— • o rH i—1 rH • rH i—1 • r-~ • 1 —1 • O i—1 rH 0 <0 <»H O rH d TO © 0 rH 1A o O CO • i—1 rH iH rH o 0 O 1—I rH i—I CA • o 1—1 d rH rH i—) o 1A • CM rH rH 1 —1 GO • O CO d O O CA iH i—1 • CM rH -P cd bD « 0 vO ♦mH O rH 0 Cd 0 • 0 • rH I—1 o nO vO CO o rH O • o «—1 XA • (A o • CA rH -P © cd pq A- CM • O 1A • O rH rH CM • CA CO • • co • rH (A 1 • CA o * CO CO 0 o *LA «• 03 © p cd © p o CO 1 d * CO i—! • CA vO 0 CO • CA • CO 1—1 Tj A 0 © © U EH rH CM CA © © £ P © d © to cd U © 3 D 03 cd © CO • o 1 rH CM co d 1A ® « Q • CO • t-q • bO cd 0 • © tfl t> o 0 1A CA rH CM TA CA rH rH 39 are included in Table 7 and Figure I * The gradual increase in sugar content of the cherries during the prolonged harvesting period in 1952 was very similar to that of the soluble solids content (Table 5) and total solids content (Table 6)* The correlation of 1952 data of soluble solids content with total sugar con­ tent on different dates of harvest was highly significant (r = 0.923) (Figure I V) o The average sugar content of the fruit decreased from 11.7 percent on July 14 to 11.1 percent on July 17# It continued to drop until a low of 10.7 percent was reached on July 21 after which time it returned to the former level of 11.1 percent on July 24* This decrease in sugar content was probably due to the rain received daily in 1952 from July 1 4 through July 23. The effect of this rain appeared to be reflected also by the variations in the average number of fruits per 45kgrams (Table 1) and to a less extent by the slight variations In the average transverse diameter (Table 2). The effect of rain was not reflected to the same degree by the other measurements made on the fruits* Specific gravity of fruits The average specific gravity of cherry fruits harvested on different dates during the commercial harvest season in 1952 increased significantly from 1.053 on June 3 to 1.068 on July 7 and to 1.078 on July 14 (Table 8). After July 14 13 12 11 10 Percent total sugar ^ 0 13 15 16 17 18 19 20 21 Percent soluble solids Figur© IVo Regression of percent total sugars on the percent soluble solias of sour cherry fruits* Fruits harvested twice weekly from four Montmorency cherry trees in 1952* (E = l c 5 7 X + 0 . 5 8 ) (r = 0 o 9 2 3 ) CM ON SPECIFIC GRAVITY OP SOUR CHERRY FRUITS IN 1952 -= t CM rH CM Pi—1 co o CA CD • rH O « rH CA P*o • co CM o • 1 —1 1 —I o o vO CO CO o rH • rH o O CO CO vO O CO CO rH 1 —1 o <—1 CM CO O • rH XA CO O • rH rH CO o o i—1 fA vO O o i—1 CA P*“ o PP- CA CO O • i—1 AO • i—1 CA vO O • rH CA vO O * rH o o o • o « rH • 1 —1 -p ca © »> U CCS >> d i rH -=f b£ •H G O c i ccS td Vi O t —1 *“D 03 © +3 © P O i—1 -P 03 aS fd EFFECT OP TIME OP HARVEST r— CA PO • rH xa o OO vO O • rH i—1 p- vO C— • rH vO XA O r—1 1 —1 CA PO • i—1 -d * p*- CA XA O • rH CM PO • i—1 o O' vO O • i—1 CO • rH oo o« i—i 9 ca CA rH O * ca rH vO O XA vO * o• rH rH ~d* XA O » «— 1 CA XA O CO XA O o 1 • • i— 1 rH rH CA O O • © *3 o 3 ca -d- o * r—1 oA vO O • i—I P_d “ o • rH i— 1 vD O • ■—1 1 ] CA XA O • i—1 o 1 XA 9 © © Ph Eh i—! CM CA • © > < Q • m • id k2 there was no significant change# These variations in the average specific gravity of the cherry fruits were very similar to the variations of soluble solids content, total solids content, and total sugar content (Tables 5-7 Inc#)# The variations in specific gravity data for fruits from individual trees on any one date of sampling corres­ ponds very closely with those found for soluble solids, total solids, and total sugar# Also, tree 3 consistently produced fruits lower In specific gravity than trees 1, 2, and on any one date of sampling# Effect of Organic versus Inorganic Spray Materials on Physical and Chemical Changes of Sour Cherry Fruits The results of studies made on the Michigan State College Horticulture Farm, East Lansing, of organic and Inorganic fungicides, showing the effects and these chemicals combined w ith organic and Inorganic insecticides on the development of sour cherry fruits are presented in Tables 9- 12 # Number of fruits per U-SU grams Xn 1952, the specific combinations of spray chemicals used on eight-tree replicates did not significantly affect the average number of fruits per 1^54 grams during any of the three periods of harvest, made at weekly intervals (Table 9A) • However, there is a trend in the data which indicates that the fruits harvested from each spray treat­ ment were heavier at the end of the picking season than at k3 O •(H T—# a 5 HP nQ CM to to t> rH Pi i— 1 ft 333 3 n p o o O O C MtO COi ft < 1 3 03 P-U _ -H- n VP tO i— I rl P ON to o 4 3 --vO i P 03 H H H H i— 1 ON to -H-vO rH rH to P iH CP p to H a + •H O * “5 i d f3tP 0 0 -P ■3 X f t ■rl ft ''M -H -vO i p n r l H i— 1 ft h O ffi a O IIi—1 4 P, , ft u nj 2 { C Q cp cm nO Cu CD -p (D b! Ri (D Ph(D Cl P tO to P cp to C MO P i> P >P U NP H H H H CM P rH vO H tO H tO O Ncm P'>± ^ P £> n rH H H tO X Ph « — I 03 •H O oi ft o + ^ 03 P CP rH to p I—1 -P 4^ f t *+- ft cd 03 F p CP I —I p CM rH 3 £ rH a gS cdcd ^ tiO fi •H [Q * C O pi % cq -p t o 0 3 E H M W o) n ft H 03 1 03 03 -f ft p| rH + O ON o E> p p -c o p l— I I— 1 r~I i— | tO O nO NvO ■ •< ? -P P P I> NO -Mp nD up rH rH H H H H fts 0 JH Pi w i —i nD q o i '>±vOI ■P U p1 H H i— — O nO C MC M -q- P vO P IA N ^ p i —!nD -uj" up p p p i —It—Ii—Ii —I H H H H CP O vD P rH rH -uh up rH z> P UP •rl |r~ r I —I -P •H 0 O D <*■ -Hr On rH C 3 H- 0 U CM £> P CP rH rH £> P -P 0 f— l i-H C S tn a 0 O -ntvO r— | p ? i— ^ IJ i—I h s t— J rn ON ON H CM PnO nQ tO i— I i— I i— I i— I P P £> P i —I i —! £> p t UP i —I I> CP ^3 ■u± P rH rH o •• m V OH A H C\ -4 C~- xO H H H H nO CO CO i—I -o- P P Md i— 1 rH i— I i— I -Mp rH 0 *§ n £ >tO - hD s 0 P vO £n- CO 0 to C D •• ft 0 0 0 D t> u 0 c d ft jJ 0 P > 0 C j O y —i -p 13 c c i P 0 C D ft ft -p to H rO rH rH nO \Q i —ti —I > I • *P 0 NrHO 0 *§ 0 P cp p p rH rH p rH S H 0 0 0 0 P *•> -P -p 0 0 0 I —I 01 -3rH rH up O Pf E> i— I n H CM CM • Q iP • • O C OC • • rH H rH H) fti ON ft 0 tU > ft cs -p CSS I rH rH VO rO 0 to cH CM Cp S H Q h p as C Ji 0 cd 0 •H O P3 P 0 H g 0 > 44 the beginning* Comparing the averages of all treatments at each time of harvest (Table 9A)* the number of fruits per 4-54 grams was significantly greater at the beginning of harvest, 1 5 7 cherries, as compared to 14-9 cherries two weeks later* These data are similar to the findings made to determine the influence of time of harvest on increase in weight of fruit (Table 1)* Individual trees, one from each spray treatment, selected for detail study, reflected an increase in weight of individual fruits as the picking season progressed (Table 9B) which was similar to the findings shown by the eight~tree replicates (Table 9A)• However, the differences between individual trees are greater (Table 9B). Neverthe­ less, the picture shown by the replication of trees is the true picture as possible variation in tree performance is partly eliminated by the larger numbers of trees. Even though not significant, the differences in the average number of cherries required to make 4-54. grams found at the beginning and at the end of harvest were greater for the two spray treatments receiving parathion than those receiving lead arsenate* This is shown by the fact that there were little differences at the time of the first harvest July 7-10, 1952, 160 cherries for fixed copper plus lead arsenate, 1 5 6 cherries for fixed copper plus parathion, 1 5 4 cherries for ferbam plus lead arsenate, for ferbam plus parathion* and 1 5 5 cherries Two weeks later the change was kS slight for the treatments including lead arsenate, 152 cherries for fixed copper plus lead arsenate and 151 cherries for ferbam plus lead arsenate, while the change was much greater for the treatments including parathion, llj_7 cherries for fixed copper plus parathion and II4.5 cherries for the treatment ferbam plus parathion* Differences of this nature are not reflected by individual tree data (Table 9B) * This may be expected owing to possible variations of single trees* The added reduction of number of fruits per grams during the period July 21-2lj_ for all treatments was probably the result of the daily rainfall from July li+ to July 23* and the 1 * 0 6 inches of rain received on July 23, 1 9 5 2 * reduction of number of fruits per l±5k- The grams as influenced by this rainy period was shown also in the detail study of increase in weight of fruits (Table 1 0 ) * Xn 1951 the cherries in the replicated plots were sampled at only one time, during the first week of the prolonged harvest period, nevertheless it seems desirable to compare the differences in weight of cherries of the various spray treatments for the two years 1951 and 1952* Thus the first time of harvest, July 7-10, 1952, was chosen for the comparison with the results of 1951* These data are given in Table 10* The trend of influence on weight of cherry fruits by spray treatments was similar for both years except that in 1951 the cherries sprayed with ferbam plus lead arsenate and with ferbam plus parathion were significantly heavier 46 CM XA a 0 •H d THE EFFECT OP FIXED COPPER AND FERBAM WITH PARATHION AND LEAD ARSENATE NUMBER OF SOUR CHERRY FRUITS PER 1+54 GRAMS ON THE p On rH CA O 'r H CM PT-d-CA-d* XAMDvOCO i—I rH rH i—I 'LA ■LA CO d * rH 1 cd a cd 1--1 Pn ■LA 0 rH C— nO rH CM XAXACM (A _ _ j. i— I i— I i— i i— I rH 1 —1 § A a © © CM P XA cd O ' C5 rH 0 vO rHtArH — 5h © a cd 1—1 Pn XA On 1—1 CO rH-d*CJN tr \v O X A r ~ rH rH i—I rH 0 0 " CM CM X A X A o -v O 0 0 0 CA vO 1— 1 bO 0 a © P > O p. 0 0 0 p a 0 © bO TJ p «al nO 0 rH S rH P 0 © CM CM 0 EH 0 © 0 © p © P a a T* s a O co © © © 0 ON 1 fee. XA a 0 0 *H a ♦ P • CO « 0 o , id E O O k l than the cherries sprayed with fixed copper plus lead arsenate and with fixed copper plus parathion# There were no significant differences between the results from the spray treatments in 1952* The growing season prior to harvest was drier in 1 9 5 2 than in 1 9 5 1 * Because of this there was some indication the dry weather may have had a greater influence on the weight of cherries in 1 9 5 2 than the spray treatments* This appeared to be true by the data on cherry weights obtained later in the season. As pre­ viously stated, cherries from the treatment ferbam plus parathion were heavier than fruits from the other treat­ ments after the period of rain during the harvesting period of 1 9 5 2 , while there was very little difference in weight of cherries between treatments before the rain* Soluble solids content The use of the organic fungicide, ferbam, with an organic insecticide, parathion, in the spraying schedule on sour cherries reduced the average soluble solids content of the fruits when compared to the soluble solids content of fruits from plots sprayed with fixed copper plus lead arsenate, fixed copper plus parathion, and ferbam plus lead arsenate* But, the differences between these last three spray treatments during any of the three periods of harvest were only slight (Table 1 1 A ) • This same effect of spray treatments on soluble solids content of fruits was shown also by the similar trend of the data obtained from U.8 a o CM H OJ* tH“ tO MO UP H H i —Ii —J •H 43 -CPd SH s. a m3 -P cd cs ci -2 cd P H i — I CD o> to CM O CM O MO MO O tO r-4 r-4 CM i— I • • •• Eh 4- F -t cd o ca O cn E h 13 C M UP 6-Q H O C O rH PI o o M a 5H (h0) i'H aa P4 fH pa pu, S O H i-P 'H a a a ,H £ Pi P ii pa i— H PH -r-f* H CH H a m i5 B P-. PH C O PH o PH H H S3 C O -4 cD p m P a £> H iH P I cd UM Eh *H -P to cd :> l~3 M 3 03 M *rf Pi O O Cd CO fH M a H • * O CM • • • ♦ H H H H O i— 1 £> H rl rl H i— I i— I O CM CP rH C \ - CP CP f> C P rH rH rH O E> H CO CP O'' C M rH rH rH CO UP O CO O' CP O rH rH rH CM O CP CM CM CO • • • • O O rH o CM CM CM CM -P Up'tO C"- to to to • • rH i—I CP -p • cn rH P I a rH a 5 O • CP f> • C P to rH rH vD S 3c>- rH rH *H I EH op u p up co 4 4 4 U P O • • U P to­ 1 — 1 rn 4 i f M A P IA H H H H Up M c O H O • f> P O' P Isi —Ii —1i —Ii —I rH U P P Pi C D 40 -P C Q < D< H fc iOO c d Q !H C D C D C O !> H c d c d pq H H UP • rH • O o 9 • U P P? rH CO CM CO rH o • • tr\ j> O • mo r l H H i— i to Z> P C O I —II—Ir- i —I f-i P P O o O • CM rH • • O M 3 O l> rH rH rH rH i—1 P- -H" <— I • • • • CO vO CP O H H H H 4- H cv r o s f up m o IP- to rH « cd to 1 o -P i— P (D a • -p D a: C C D> c d E -» U P 0 •-». -P *P P 0 40 40 • 4 % PH p J Q • • H C/0 to o • «5jJ i-H PJ C O 4=J sd ro C D -P rH • • vO crH rH MO CQ £ Jh c d c o -p J c P C vl' O * • vD £> i— 1i— 1 •3 a ca CD P C D 0 co o a pq < = c j H PI o MO CM rH OP nb PM O -P f-i P > C D c d a U P $ -p ra • u P S C I C C D C D c d c~ h F-i — 1 1 F -P -P 'C O "cS d o -tp .' cQ d C C Q •P -P C D P rj 4- O ■ H n O r-H h D F Pd C D-p X C d •H Pi c f-r-, Ph fn o c d o Pi O SH HI rjl p4 Pu H 0 4- o 1 pd E h o o C O • - P H H H X O s O -f* H O a C aa « • cd O f-i m3 M 3 CD cd CD Pi rH -<*■ CM CM o •H Pd HH 49 individual trees of each spray treatment which were selected for detail study and were sampled twice at three-day inter­ vals during the three periods of harvest (Table llB)o Xn each case, the soluble solids content was lower in fruits treated with two organic compounds (ferbam and parathion), while there were no significant differences between the treatments containing two inorganic chemicals (fixed copper and lead arsenate), or with the combinations of inorganic and organic pesticides, ferbam plus lead arsenate or fixed copper plus parathion* A comparison of the results of treatments in which eight replicates were used per treatment the average soluble solids content of the fruit sprayed with fixed copper plus lead arsenate was always the highest on each time of sampling, 1 8 *1, 20*0, and 20*2 percent, while cherries sprayed with ferbam plus parathion were always the lowest in soluble solids content, l5*5» 15*2, and 18*1 percent# Xn detailed studies made in 1951 and 1952 of cherries harvested at three- and four-day intervals from the time the cherries could be first picked commercially until they shriveled on the trees, generally the trees producing cherries highest in soluble solids by comparison at the beginning of harvest continued to produce cherries highest in soluble solids by comparison at the end of the prolonged harvest period (Table 5)* Also, generally trees producing cherries low in soluble solids by comparison at the beginning of commercial harvest continued to produce cherries lowest in soluble solids by 50 comparison at the end of commercial harvest. The maximum soluble solids content was not the same for all trees of a single planting in any one season. The average soluble solids content of fruits from all treatments increased significantly from one period of har­ vest to the next, 17©0 percent during the period July 7-10, 18.3 percent during the period July l5-17> &nh 19«2 percent during the period July 20-2lj. (Table 11A). This increase was similar to the increase of soluble solids content as the season progressed shown by the detail study made in 1951 anh 1952 to determine the effect of time of harvest on soluble solids content (Table 5)* Xt was of interest to compare the average soluble solids content of the cherries from the different spray treatments Of the replicated plots found in 1951 to those found in 1952. Only one sampling was made in 1951 and this was taken the first week of the prolonged commercial harvest, the data in 1952 obtained from samples taken during the period July 7-10 were selected for comparison (Table 12). The two-year averages of the soluble solids content of fruits from the four spray treatments were as follows: fixed copper plus lead arsenate - 18.5 percent, fixed copper plus parathion - 17*9 percent, ferbam plus lead arsenate - 17.0 percent, percent (Table 12). and ferbam plus parathion - 15*9 These data showed that the fixed copper sprays had a more pronounced effect on the soluble solids content than ferbam, and that lead arsenate treat- 51 CM XA O' rH H ^ A -X A r H 1 6 • • 1 A v O f t " HD rH i—1 i—I i—1 c A X A ftc O » • • « XAXAM DXA rH rH i—i r—1 A— o XA rH rH A - CM vD f t * • • « ft* X A -ftX A rH i—1 i—1 i—1 X A A -C A v O • « • • v O M > A rH rH H H CM • HD rH CM O 'X A O D o • • • X A - f t A -v O i—1 rH i—1 i—1 lA fA C O CM o • • • [— O ' O - CA i—1 i—1 i—1 rH CA • ArH •ft iH cd X A © O' f t i—1 CO vO CO f t " • O • • c A ft'C O vO rH i—1 i—1 i—1 O rH co rH • • « • vO O vO O i—! CM i—1 r—1 A• vO i—1 CM XA CA rH CO CM CO rH • o • • V.O "LA r — O ' r—1 i—1 i—1 i—1 lA C O rH CVJ A• A i—1 G o •H ft ■ft cd G cd ft sz; xa o rH o CA o XA rH w Eh g U © ft pq co co eh « h ft PS ^ PS ft pq S io EU cd •• TO 0 K bO 0 0 •H ft Eh 0 ft c A X A ftX A « « • o v £ )\D G O rH rH rH rH O 0 XJ ft o 0 o f t CO o *& £ (H 0 CO O ftC * 0 r—vO i—1 rH pq p i 0 •• © CM f t XA cd O' G i—1 0 0 G cd P i pq O • Ai—1 G cd CO +» £ S; H « CM xa ca rH cd X A O' r—1 M rH * 0 O " r— rH i—1 rH Is— -~~J“rH * * • « COCO CA CA i—I i—1 i—I t —1 XA « CO 1—I rH • CO rH rH CO - f t • o * O O co o CM CM rH CM o • cd CO t—1 pq ft ft pq pq g ft rH © cd bO G cd O G 0 0 cd > © cd CO 0 > 0 a CD XA e rH E -p cd 0 1 -P rH cd rH C! *♦» o TO rH CA O U -P 0 0 0 tuO cd ft U cd 0 0 t> U cd 0 o 0 ft TO •i ft O XA S * o TO f t « •H CO 0 cd P. f t E o o o Ph TJ VL 0 rH G *H A CO £ o• o o <*H o XA f l o 0 ft G Cd ft e o o CO 52 ments had a more pronounced effect than parathion* However, the combined effect of an inorganic fungicide, and an inorganic insecticide, on the soluble solids content of fruits were most striking, fixed copper plus lead arsenate was 18©5 percent as compared to only 1 5 * 9 percent for ferbam plus parathion0 From these data spray materials may be assumed to affect total solids and sugar content of cherry fruits because of the highly significant positive correlations of soluble solids with total solids and sugar content (Figures II-IV inc*)© Individual Orchards The findings resulting from studies conducted in five commercial orchards, located In the Hart-Shelby area and the G-rand Traverse area, from 194-9 through 1952, are pre­ sented in Tables 13A through 17B© Data relating to soluble solids content are included In Tables 13B through 17B, and data relating to weight of cherries (number of fruits per 4-54- grams) are given in Tables 13A through 17A© Orchard A (Morrison orchard S) Number of fruits per 4-54- grams The influence of fixed copper on the averagenumber of fruits per 454- grams in Orchard A decreased from 194-9 through 1952 (Table 13A)* The average number of fruits per 4.54- grams was significantly higher in the fixed copper 53 A 03 !2? TJ © © ft X a. ft O CM XA O ' *H O A u <*j <£ ft O •• © bO cd U © > cd P £ © £ -p cd © GO £ P © © CjD © £ © > cd CM rH P £ © £ P cd © £ I^ •H £ © © ft P © £ CM C— O rH rH • Q • CO XA .• ti ' 1 cd 'iA 'sS . f t X A rH £ o © A *-X rH o o 54 treatment in 19^4-9* 1 2 7 fruits for fixed copper spray treat­ ments as compared to 116 fruits for the ferbam and nab am treatments. During the three years that followed, 1950, 1951* and 1952, no similar significant differences between spray treatments were evident. The reason for the differences in 19^1-9 may be attrib­ uted to the fact that the trees were growing in sod mulch in 19^4-9• However in 1950 the grower changed soil manage­ ment to clean cultivation plus a cover crop. This increased vegetative vigor of the trees, brought about by increased cultivation could have resulted in an increase in the size of the fruit which in turn increased the weight of the individual fruits. Observations indicated that the fruits from the fixed copper treatment were smaller than those from the other two treatments in 19^4-9o Xn 1950, 1951 and 1952, however, such differences could not be distinguished. Rainfall was ample for cherries of good sige in all four years. The increase in tree vigor in Orchard A decreased also the average number of fruits per i4S k - grams from the trees sprayed with organic compounds; however, this decrease in number of fruits per 14-5 ^4- grams from the nabam treatments was not significant until 1951 (Table 13A). Except for the decrease from 110 fruits per i4.5 i.j- grams for the nabam spray treatment in 1950 to 96 fruits in 1952, there was no signifi­ cant change in average weight of fruits after cultivation was started in 1950. The 6 . 8 3 inches of rain in July, 1952, 55 may have had a direct influence on the increase in weight of the fruit of all treatments that year (Table 21) • Soluble solids content The percent soluble solids of fruits from the fixed copper treatments in Orchard A decreased progressively from l6 0lj- percent in 1914-9 to 13*4 percent in 1952* However, during this same interval, the percent soluble solids of fruits from the ferbam treatments decreased from ll+^S per­ cent to 11*3 percent and from 15*9 percent to 13*3 percent for the nabam treatments (Table 13B)* This indicated that the increased cultivation, as it affected tree vigor, also decreased the soluble solids content of fruits from all spray treatments. The relationship between soluble solids and spray treatments was not materially affected* Kenworthy and Mitchell (19) reported also an inverse relation between the soluble solids content of fruits and tree vigor* Observations of the trees in this orchard before the experiment was started indicated that those trees selected for the ferbam treatment were more vigorous than the trees of the other treatments* solids content. This was reflected by the soluble However, the over-all findings of this study including all orchards (Table 23) indicate that the continued high soluble solids content of the cherries sprayed with fixed copper was a direct result of the spray treatment 9 The percent soluble solids of fruits in Orchard A 56 j=j a} rH • A rH cd S23 C\l 0 XA O'* •H i—1 Ph p Oq PS W (U s EH Eh O O s i od <*; m O O CQ S pq o M os Eh K m A CO l —I OS25EH w CQ pH id PQ P « « J H pq PS EH « H < PS PS & PH O CQ CO -P O d 9 • CA rH CM i—1 CM • A rH A O • rH l—1 vO • rH rH _r 9 9 XA rH A r—1 XA 9 rH i—1 d A d O' * d i—1 d f • A i 1 — vQ • XA i—I CO • d r—1 O' • d i—I XA i—1 CO • CM rH ao • CM i—1 • A rH o d CO CO • d rH O • d H C• d •—1 • -d " rH • A •—1 9 rH rH O • rH CM d O 9 9 1—1 1—1 A 9 9 d rH d rH O' O' 9 9 d rH 9 9 1—1 CM r*— 9 9 rH rH CM rH A A CO S3 s ra ra £ r2 a te Pi o ra cd © CQ A rH vO • d cd r- A d rH • CVJ rH OJ C '- • i—1 H d T3 0 rH © PL in CL O ' •H O i—i Ph o ra O' O x> d 0 Ph £cd is; CQ P pq PS P PQ W !=> & P PS d 0 CL CL O O • i—I rH XA • d rH xa Ph •o 0 0 CL XA CL O '' •H O rH PL O o 1 d 9 d i—I A i—1 A 9 U \ rH d rH XA 9 XA r—1 i—I • XA rH o- A d 9 XA rH 9 XA rH — d 0 Ph d i—1 g ra ,© i—1 9 vO rH O O C • A i—1 XA 9 d i—I CO A rH d rH r— • XA rH XA • nO rH CM 9 O 9 vO 1 1 — XA i 1 XA • O- O' d 9 9 (—1 d rH 9 9 — 9 d rH O' 9 XA r—1 o pL o 9 o CVJ • vD rH g ra n XA d © Ph d rH H 9 o d • XA i 1 — l>•XA rH vO rH NO rH • NO rH ra © d -p O' 9 A i—1 MQ 9 d i I — CO 9 d rH 0 CM A o A 9 rH 9 CM d 0 0 9 rH ra ra o0 cd d 0 t> ra -p -p d 9 o «• 0 bO ra Ci © > d XA > <*i O CO S3 o O ra *rH t d • 0 rO CM 9 rH I cd ^ ^ P j X A rH • CQ • -P £ © i -fP cd © -P <5h £ -P Q 0 0 d E O' ci 0 is; O' © d O ' •H rH E— 9 XA rH d < O ' CA © © bO © 0 © > © ■P XA H © © bO © 0 0 © © > © 0 B.p © 0 £3 © •-ep Q © •© CO 0 • -P i-3 0 © S © © 0 -P rH LA <0 I I O 0 XA rH O © * •H Q «l CO §* o o 59 trees sprayed with ferbam as compared to the fruits from the other treatment© As the years progressed the trees sprayed with fixed copper produced cherries progressively lighter in weight© B y contrast, the weight of cherries from the treatments ferbam and nabam changed but little. This could have been due to the physiological effect of the fixed copper on the vigor of the trees, reducing the vegetative vigor of the trees© Before starting this study, the entire orchard had been sprayed with ferbam for more than five years© Soluble solids content The average percent soluble solids of fruits from trees sprayed with fixed copper was significantly higher than that of fruits from trees sprayed with ferbam in 191+9* 1950 and 1951* and significantly higher than that of fruits sprayed with nabam in 1914-9 (Table ll|3)© The differences in soluble solids content between spray treat­ ments were: in 1914-9 ferbam 1lj.©2 percent, fixed copper l£©f> percent and nabam 13©9 percent; in 1950, ferbam 13*9 per­ cent, fixed copper 15*0 percent; and in 1951* ferbam 13*1 percent, fixed copper l5«2 percent© There were no differ­ ences between the soluble solids content of fruits from the fixed copper and organic spray treatments in 1952© This may have been due to a reduction of the influence of fixed copper as a result of the increased rainfall of 6 *8 3 inches during July* 1952 (Table 18)© 60 § 43 © 123 TJ AJ XA EH O Pd © X 0 s •H rH Pi © P Cl © O i—1 • o • vO * P~ • XA ♦ CA rH vO rH AJ rH CM i—1 AJ i—J CA i—t d d • o xO • CA * O • P• XA * p « XA XA rH d rH AJ i—1 CM rH AJ rH CA i—1 rH C\J vO • c— • XA • rH • d • O e AJ rH AJ rH cA rH CA rH CA rH cA i—1 CO • AJ « CO • CO P0 CA rH vO rH -d rH d rH CO • cA rH CO • CA • CO » XA • P* 'LA XA rH d rH CA rH CO • XA i—1 CM o vO i—1 XA rH (—1 C\J rH o AJ rH O • cA rH Po Pe •—1 • cA rH AJ rH CA rH m Ph j Eh Ph & © Ph W Eh lS« O O 43 CO Q a O © PQ CO TJ Q pq W as pq a < EH -p 09 O o co > W o ( —I rH XA B « s 3 w « S CO 0 EH CO £5 —I bj P>qW EH PS < pq g W cd g £3 Ph © P P O O © o 43 Ph © Ph u © d • d rH 09 d CQ a o ■s is ; © ® CO d o O • d cA rH vO rH d rH ® CO * cA i—1 rH • CA « o d rH d i—I Ph t3 © CA • O • o d rH XA rH XA rH O • CO * d P XA W P O ' •H O XA rH d rH XA rH O • CVJ • C "— • O • CO • O ' • d i—1 d rH cA i—J d rH CA i—! cA rH o © i —IPh Ph © Pi ° d • 43 © • CA rH d l O ' • CA « P O ' *rH O Ph O o • O'— 1—J *H—I © > © -p H H © S 43 © © P. A CA • CA i—1 CA * 43 d rH AJ i—1 Ph © CA o P* XA i—f CA rH O ' • d rH AJ » d rH Ph rH AJ CA d XA © CO > <*1 © XA rH Ph ♦ © O rH •H I I O w n © © £* o d 43 « © © P ft 0 P o OQ d o 03 rH i 1 rH — P cd is; cd aS -P d 0 -P d © £ ft •r l O *8 © > CA rH CO 1 1 rH — O CM rH O' i—1 i—1 CM rH H — i 1 OJ rH -p cd 0 rH rH -P ft £ p nO (—1 d © © •» CA CM rH CA rH i 1 — OJ O iH cA rH rH -d * CM i—1 L f\ r—1 rH o -p © ■P • © 0 ft &H o rH OJ CA -C± LA 0 t> < • ^ CQ L A • aS © ft i *i •H rH Cl H d O i—1 rH 0 •H 1 1 ft cd P L A rH £ O O 63 per grams In 1952 in the organic spray plots was probably due to similar cold injury which occurred in early November, 1951* Apparently in 1950 dormancy of trees sprayed with fixed copper was delayed as compared to trees sprayed with the organic compounds resulting in injury by the early cold weather# The fixed copper sprayed trees held their leaves into October while the trees of the other treatments were almost completely defoliated by September 25> 1950* There were no differences In the Influence of spray materials on the number of fruits per g**ams in Orchard C, except for the injurious effect of fixed copper which appeared to be related to cold Injury in 1950* Soluble solids content The percent soluble solids of fruits from trees sprayed with fixed copper was significantly higher than the fruit from trees sprayed with ferbam and nabam in 19i|-9 and 1952 and was significantly higher than the fruit of the ferbam treatment in 1950 (Table 15B)# In 1951 there was no difference between spray treatments, which could not be explained unless the cold injury mentioned previously reduced the vigor of the trees sprayed with fixed copper and the resulting fruit was smaller in size than the fruits from the other spray treatments# Actual observations of the fruit would verify this explanation* The effects of increased rainfall In July, 1952, on 64 6 o fO GO S3 73 ra C\J W •H O ' ft S3 XA o rH Ph W • CA <—1 XA ♦ AJ rH O • OJ i—1 XA • AJ i— 1 XA r—1 rH o AJ i—1 XA • ArH AJ • vO i—1 o d CA • CA d * O © XA 0 XA p—| i—1 rH i—1 d CO • fA d rH AJ • cA i—1 CO • AJ i—1 AJ • cA i—I rH • cA O • CA i—1 r• AJ d fc ra A ft O ra 0 * XA i—J d i—I XA • CA -P H ra ® pq Eh K SB ^ pq PQ 73 ra W •H JjL, ra ft ft o ra l > U d Gi ra Ph d cd ra bO cd £ £ CA 0 AJ rH d CO • d i—1 XA • C\J rH CA • AJ rH CA • CA i—1 rH 0 A i—1 CA • AJ i—1 rH • XA i—! i—1 « d i—! CA • cA rH C"— • d rH cd ra £ -p d £ ra ra S pT( o ft •* ra cd d cd S3 & AJ • cd -P £ ra 8 +3 AJ o AJ iH 0 XA rH XA o d i—1 CO • cA rH AJ • d rH rH » AJ rH • (A rH rH • rH vO 0 rH ra d rH AJ ca d XA n 9 CO XA • *-3 43 £ ra 8 43 cd ra £ -P ft o • » ra > < -p £ ra £ ra <£ Ph CO S3 o d g Ph CQ CQ pq CA • O rH . _ d £ • O rH ra •H I £ cd ^ f t XA 8 o o AJ e AJ 65 the percent soluble solids content of fruits was not apparent. If variations in tree vigor did exist in this orchard, such variations were not reflected by the soluble solids content of fruits; except perhaps for the decrease in soluble solids of fruits from the fixed copper treatment in 1 9 5 l© The percent soluble solids of fruits in Orchard C did not appear to be related to the number of fruits per k-5k- grams. This was verified by the fact that in 1951 the number of fruits per grams varied significantly, 118 for the ferbam treatment, 1 3 6 for the fixed copper treat­ ment and 1 1 3 for the nabam treatment, while the soluble solids content for the fruits from these treatments were 1 2 .I4 percent, 1 2 . 7 percent and 1 3 * 1 percent, respectively. Orchard D (Stokeley orchard) Number of fruits per h5h grams The number of fruits per grams in Orchard D was significantly higher for trees sprayed with fixed copper than for trees sprayed with ferbam or nabam in 19il9> 1 9 5 0 and 1 9 5 1 t hut was significantly lower than fruit from trees sprayed with nabam ih 1952 (Table 16a)♦ The increase of average weight of individual fruits from the fixed copper treatment in 1952, from 129 fruits to 108 fruits per 1^.54 grams, was probably due to the excessive rainfall (7 ©^4inches in July) in 1952 (Table 16a)© The reduction in the intensity of copper injury on cherries, in years of high 66 1 _Q r~j cd CA CM iH XA rH r—1 CA CA rH sO rH rH XA rH rH CA CM rH TJ 0 C\J 0 04 X A w 04 O '* *H O rH o XA rH rH CA CA AO rH rH rH rH \ D O rH CO O rH X» Pi 0 rH O rH vO O rH AO t—1 rH CM r—1 O rH rH CA O i—1 A— CA O O rH t—1 O i—1 CM O rH CM O rH o o 1—1 rH 0 0 , XA W . 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PQ vO rH W E-h » in rH O • €© d Ah d lf \ rH fa o TO d O CO © o m rH in CM • CO • d O' rH d © © ft «* ft *H O (x, O lii © Eh o0 d 1 in rH -d * o xO rH • nO i in (—o1 in (O' # in rH CO • Is— rH • NO <—1 in nO CO CO ON rH O' 1—1 C“* CO rH CJN 0 CO — 11 cd © TO -P d a V d CM o rH vO o • d • in • i—i vO i— i C— • NO rH in • d d xO rH xO rH NO rH on o CD rH d CO CM • CM • rH i — • rH O ON • rH m rH NO • GO rH r—1 * OrH on rH m nO rH rH • NO —1 1 0 • CO rH • CO i— 1 CJN a CO rH 10 d • # rH On in 0 rH d o 0 rH ON rH rH • o- •• rH CO • co 0 rH On o CO • CO i—1 CM rH rH O• o CO rH rH 0 CM • vO rH xO • xO rH ON o d r*H o • ao rH on • nO rH r— 0 vO i—1 © bO © bo © > © © © Ft © d > © -P £ © -P d © -p cd on © -P ♦ rH ON 0 rH rH CM on d in © e © © d -P © © Ah O -P d © o © d •rl d • 0 © Ah Ah •H Ah O •• © d © d xO 0 CM in O ao o CM ■©8 CO 0 —1 • x£> i—1 125 TS 68 on • on rH • vO rH o 1—1 in • CJN • CM rH o in d © on o • rH p^ tJ © © P* « & •H o Ph o ao O UN rH rH vO -d " CM rH rH e co 43 ?H © (H M3 rH t—1 CO § Pi o 43 cd !2! cp OJ cd rH i—1 *• © P o! © © © © o (Xj a s TO cd rH ao CM 1—1 rH rH r—1 rH rH rH UN rH rH CO r—1 rH 43 © CO O UN u TJ © © P, P, O ' •H O i—I Ph o O © P=H g TO 43 rH iH r— rH i—1 ao i—1 UN -d" o CM UN CM rH rH -d " rH CP r—1 -d * rH rH CP iH cd is; O i—I rH CM Pi O' O' UN rH rH 43 fP oO' rH rH O -d - o rH rH T—1 rH rH O CM rH UN i—1 © 50 ad Pi © > cd CM CM P r—1 C © E 43 43 cd TJ © X •H rH pH O' _d g 5 o tJ © © p., & o © sO CM rH o vO -d * rH CP <~P rH rH CM t—1 O' CP i—1 UN OP i—1 O' CM i—1 o CP rH O' CM rH rH cp rH CM cp cp rH rH cp P cp -P rH CO rH Pi © © > 43 © 43 rH CM cp -d - UN o © > <3 a • ^ CO UN • © £ 43 © © u 43 • 4) © <5-i O Pi o CP —1 i—! o © 1 •H t 1 © a i—1 s o o un iH 71 The number or fruits per 454 grams from trees sprayed with fixed copper was significantly smaller than for the trees sprayed with either ferbam or nabam in 1950* and smaller than the number of fruits from trees sprayed with nabam in 1951 and 1952 (Table 17A)« There was no significant differ ence between the ferbam and nabam treatments for any year In this orchard. There was, also, no significant differ­ ence between the fruits of the three spray treatments in 19490 The number of fruits per 454 grams from the trees sprayed with ferbam decreased progressively throughout the study; from 133 fruits in 1949 to 120 fruits in 1950 and 107 fruits in 1952* The number of fruits per 454 grams from trees sprayed with nabam and fixed copper did not change significantly from one year to the next* The data for the trees sprayed with fixed copper in 1949 should not be compared with the averages for the fixed copper treat­ ments from 1950 to 1952, because new trees were selected by the grower for this treatment in 1950* These newly selected trees were smaller and more vigorous than the trees sprayed with organic fungicides* This progressive increase of fruit weight in the ferbam spray treatments seemed to indicate a greater response of the tree to the spray treatment than trees sprayed with nabam or fixed copper* This orchard was in a low state of vigor two years before this study was started and the grower was using heavy nitrogen applications to increase yield* 72 Soluble solids content The percent soluble solids of fruits from trees sprayed with fixed copper in Orchard E was significantly higher than that of fruits from the ferbam or nabam treatments in 1950, and higher than that of fruits from the nab^m treat­ ments in 1952 (Table 17B)<» The general uniformity of the average percent soluble solids of fruits in the different spray treatment of this orchard may have been due to the high state of vigor of the orchard owing to the high annual rates of nitrogen fertilizer used to maintain production. The progressive increase in percent soluble solids of fruits from each spray treatment, from approximately 13*0 percent in 19it-9 to a high of 15*0 percent in 1951 > followed by the sudden decrease to approximately 12.8 percent in 1952 may be explained by corresponding changes of rainfall during that four-year period. The changes in total rain­ fall for June and July were from ?.02 inches in 19^9 to lj-.97 inches in 1950, lj..l6 inches in 1951 and 8.58 inches in 1952 (Table 18). The percent soluble solids did not appear to be related to the number of fruits per kS k grams in Orchard E, because in several instances an increase in the number of fruits per l4.Sk- grams was accompanied by an increase in soluble solids, while in other instances, the increases in number of fruits per in soluble solids0 k 5k grams were accompanied by decreases 73 O' rH CM rH C\] rH "LA • rH rH i—1 • CM rH rH • CM rH rH • CM rH "L•A i —•I CM cA rH rH Is* fA CO • CM CA * d CO "LA rH "LA rH -d rH CO 'lA co* a -d U \ rH i —t -d * rH O' CO O d" rH -d d LA CA • d i—l • cA (—1 • * CA sO (H i —1 ArH • • d od P © Jit -d * vO rH i—I O (0 a CO • CA rH P o cd $2; 09 cd © > cd © p d 43 e © © Ci © p P O O © £ in * CM i—I ■s {23 sO * 1A iH • rH« CO 0A cA -d * I —I rH pH d vO CO © O' © -d X O •H pH O -d * CM « • "LA vO vO d 43 O ♦ d iH CA <» CA rH CM • d rH o • CA rH CO • CA i—1 A• CA rH S cd d © Pi 43 43 © • rH CM © d 43 O © ■e © O • CM rH O • cA rH CA • CM rH O • CM i—1 Ao d rH CO • OJ i—1 © O * © P d o © Pn © © Ci Eh • © rH CM CA d * "LA > < S P • 50 1 A P P E o o O • "LA• rH rH I I ^ V?. "LA rH 7k TABLE 18 INCHES OP RAINFALL RECEIVED DURING MAY, JUNE AND JULY OVER THE PERIOD 19^9 THROUGH 1952 IN THE AREAS INDICATED Traverse City May June July Hart-Shelby May June July East Lansing June July May 19U9 1.60 3 .6 2 3 o08 1 .1 1 3.48 3.5k 2.3*4- *1.89 1950 1.85 1 .7 0 W O 1 .8 0 2.55 2 .1^2 1 .9 6 I4..71 1951 2 .0 0 1 .9 2 3.-21* 1.35 2 .1 8 1.97 3 .0 8 3.27 1 .0 7 1952 1 .7 0 3.2*4. 6 .8 3 3 .0 0 1 .1 6 7.40 W 8 l.ij-6 3.24 3.75 3.37 2 ,2 8 Normal rainfall for 30-year period k * 79 75 Combined Results from Five Commercial Orchards The combined results from five commercial orchards showing the average number of fruits per I4.5 I4. grams are given in Tables 19-21 and the average percent soluble solids of fruits are Number of fruits per presented in k.%k. Tables 22-2lj grams Effects of spray chemicals; The use of fixed copper as a fungicide increased the number of fruits per l^l^. grams when compared with fruits sprayed with ferbam and nabam in Orchards A, C, and Do This is shown by the averages for the four-year period in Table 19 0 average number of fruits per In Orchards B and E the grams was significantly less for the fixed copper treatments than for the ferbam and nabam spray treatments, 1 0 9 fruits as compared to 1 1 9 and 1 1 8 fruits from ferbam and nabam spray treatments respectively in Orchard E, and 113 fruits for the fixed copper spray treatments as compared to 119 fruits in the ferbam spray treatments in Orchard B • These results in­ dicated that the injurious effects of fixed copper sprays was decreased by the increased tree vigor heavy applications of nitrogen in Orchard resultingfrom E andby contin­ uous cultivation and fertilization in Orchard B* High vigor was maintained in Orchard E by "trashy11 cultivation and heavy applications of nitrogen while Orchard B was clean cultivated and received moderate annual applications of nitrogen and barnyard manure 0 76 TABLE 19 INFLUENCE OF FUNGICIDAL SPRAY MATERIALS AND ORCHARD VARIATION ON THE AVERAGE NUMBER OF SOUR CHERRY FRUITS PER GRAMS DURING THE PERIOD 19*4-9-1952 Spray material A Orchard D C B* E L.S.D. between orchard averages within a treatment 5% 1% Ferbam 102 119 120 116 119 5 7 Fixed copper 11^ 113 126 125 109 6 9 Nabam 105 11*4- 119 111 118 7 10 L.S*D. between treatment averages within an orchard: 5$ 6 6 5 *4- 5 8 9 7 5 7 ■*Data for 19*4-9 not included for Orchard B 77 The inter-relationships of effects of variations in seasons and of spray chemicals on the number of fruits per kS k- grams for the five commercial orchards are shown in Table 20* In 19^9 the differences were significant between the average number of fruits per grams for the spray treatments, 1 1 7 fruits for the nabam treatments, 122 fruits for the ferbam treatments, and 128 fruits for the fixed copper treatments* These differences could not be explained on the basis of the known seasonal conditions and thus were assumed to be the results of the spray treatments* However, the significant increase of average number of fruits per 14-54- grams of the fixed copper treatment in 1951 was ob­ viously due to the pronounced increase in Orchard C which was considered to be the result of cold injury occurring in November, 1950* It is interesting to note that the grand average of number of fruits per grams of each spray treatment in the five orchards, which includes the four seasons, was not significantly different, 112 fruits for the ferbam treatment, 115 fruits for the fixed copper treatment, and 112 fruits for the nabam treatments (Table 20)* This indicated that the effects of spray materials on the number of fruits per lj-5^ grams was dependent upon climatic factors and tree vigor as related to fertilizer application and soil management'. The differences resulting from variations of seasons for any one orchard were as great as variations resulting from spray treatment* 73 TABLE 2.0 THE INFLUENCE OF SPRAY MATERIALS AND SEASONAL VARIATIONS ON THE NUMBER OF SOUR CHERRY FRUITS PER 4-54 GRAMS IH FIVE COMMERCIAL ORCHARDS Orchard 19*1-9 - Spray treatment Ferbam Fixed Nabam copper 116 A B C D E Average L.S.D. A B C D E 117 103 118 117 120 120 113 107 117 129 110 115 113 111 104 118 115 114 113 95 119 I lk 113 115 136 129 103 99 113 113 100 119 112 119 109 103 117 131 99 112 96 113 132 123 113 115 115 112 118 115 - 7; L.S.D* between treatment averages 5% 1% 8 P11 8 13 12 — 16 12 13 9 6 6 10 19 13 9 9 15 18 27 23 18 «» vO 1952 5% 128 1 A B C D E Average L.S.D. 122 rH A B C D E Average L.S.D. 5 ^ - 5 195l 121 134 131 115 Average L.S.D. 5% - 5j 1950 123 133 116 — 118 112 122 127 — Seasonal average 114 16 16 7 24 16 11 24 10 12 9 13 10 1417 Ik l8 15 113 w "cA 1 H O Season 9*4120 130 109 107 112 Treatment average '' 112 L.S.D* 5 ^ - 9 108 113 **1914-9 data omitted from the treatment average because the size of fruit In Orchard B was not available 79 Effects of orchard management: The significant de­ crease in the average number of fruits per Lj.54 grams from the ferbam and nabam spray treatments of Orchard A (Table 19) was apparently due to the progressive annual increase of tree vigor which resulted from the change from sod to clean cultivation in that orchard* Application of fertilizer, pruning and soil management, as they affect tree vigor, are apparently responsible for much of the variation of the weight of cherry fruits* average number of fruits per The grams in Orchards A, D, and E was significantly less in 1952 than in 19lj-9» when the trees in these orchards had reached their highest state of vigor (Table 21)* The average for Orchard C was excess­ ively high in 1952 because of the cold injury to the trees in 1950 and 1951. Effect of variations in seasons: Variation in seasons had no effect on the over-all average number of fruits per l± 5 k grams from all spray treatments in the five orchards* This was shown by the figures, fruits in 1951 and lllj- fruits in 1950and 113 1952 (Table 20)* The increase in average number of fruits per grams in Orchard 0 in 1951 and 1952, from 115 fruits in 19i+9 to 122 in 1951 and 131 in 1952 (Table 21) was apparently due to cold injury in 1950 and 1951 » as explained previously* The consistent decrease of number of fruits per grams from Orchards A, D, and E (Table 21) from 19lj-9 through 1952, was probably also the result of increased tree vigor and not variation in seasons. 80 TABLE 21 EFFECT OF SEASONAL AND ORCHARD VARIATIONS ON THE AVERAGE NUMBER OF SOUR CHERRY FRUITS PER \\5 k - GRAMS FROM FERBAM, FIXED COPPER AND NABAM SPRAY TREATMENTS Season A B 19i|-9 120 — 1950 109 1951 1952 Orchard C L.S.D. between orchard averages within a season 1% D E 118 123 129 6 9 113 115 120 111*. 6 8 102 115 122 115 112 9 12 98 117 131 113 106 7 9 L.S.D* between seasonal averages within an orchard •• 6 6 6 ij7 5* 8 9 8 6 10 1% 8l The absence of apparent effect of moisture on the average number of fruits per grams was not surprising, as the rainfall was adequate for good cherry production during each of the four seasons# Soluble solids content Effect of spray materials: The use of fixed copper resulted in a significant increase of percent soluble solids in Orchards A, B, and C as compared to the soluble solids content of fruits from trees sprayed with ferbam, and in Orchard E as compared to trees sprayed with nabam (Table 22)* In all spray treatments the percent soluble solids of fruits from Orchard D was approximately 3*0 percent higher than the soluble solids content of fruits from the other orchards* This was apparently due to delay in time of harvest in Orchard D each year as compared to time of harvest of Orchards A, B, and C* In the detailed study at East Lansing a delay in time of harvest was shown to increase, significantly, the percent soluble solids of the fruit* In 1952 the high rainfall resulted in a reduction of percent soluble solids in fruits from all spray treatments and reduced the tendency of fixed copper to increase soluble solids of the fruit, because the differences between spray treatments were not significant In that year (Table 23)* However, an increase of soluble solids of fruits from the fixed copper spray treatments was shown by the averages for 82 TABLE 22 THE EFFECT OF SPRAY TREATMENT AND ORCHARD VARIATION ON THE AVERAGE SOLUBLE SOLIDS CONTENT (PERCENT) OF SOUR CHERRY FRUITS (1949-1952) B L.S.D. between orchard averages within a treatment 1% 5% E 2 .8 14.3 14.1 13.1 16.1 13.3 1.7 2 .3 Fixed copper 1 5 .0 1 4 .8 Nabam • 2 .0 13.3 13.6 13.0 15.9 L.S.D. between treatment averages within an orchard: 0.7 0.9 1.3 1.4 0.9 1# 1.0 1.3 2.0 2.2 1.3 • 1 4 .4 1 7 .0 1 4 .4 Ferbam 0 1.5 CM CD A Orchard C D H Spray material 83 TABLE 23 THE INFLUENCE OF SPRAY TREATMENT AND SEASONAL VARIATIONS ON THE AVERAGE SOLUBLE SOLIDS CONTENT (PERCENT) OF SOUR CHERRY FRUITS (1949-1952) uwctoon 1914.9 111-.8 14.2 13.it 16.7 12.8 A B C D B Average L.S.D. lit.it A B C D E A B C D E Average L.S.D. $% - 0.8 1* « 1.0 1952 15.5 14.7 18.5 13.7 15.7 15.9 13.9 12.9 16.1 12.5 14.2 L.S.D. between treatment averages if o v$> 1.3 1*3 1*1 1.3 1.4 2.0 1.9 1.6 1.9 2.0 0o7 0*9 1*2 1.4 0.8 0o9 1.3 1.8 2 .1 1.2 loll1.7 0.9 1.0 2.4 2.0 2.5 1.4 1*4 3.5 1*4 1.7 1.0 1.8 0.9 2.0 14.8 0.8 1U.0 13.9 12.9 17.1 14.0 Average lit.it L.S.D. $ $> - 0.5 if o - 0.6 1951 16.4 Seasonal average - 0.6 - 1950 Snrav treatment . Fixed Nabam copper urcuai A B C D E Average L.S.D. 5?o - 1.2 if 1.5 15.4 15.0 14.8 19.8 15.6 16.1 14.3 14.3 13.9 18.9 13.7 15.1 12.7 13.1 12. 4 15.9 15.0 13.8 14.9 15.2 12.7 15.8 15.1 14.8 14.3 14.7 13.1 15.9 15.0 14.6 11.3 13.0 13.4 14.0 13.4 13 .1 13.4 13.5 15.4 14.1 13.0 13.9 13.3 13.4 12.4 13.3 12.1 12.9 L.S.D. between yearly averages • 1.8 1.3 2.5 15.2 1 4 .4 2.5 1.5 2.6 1.2 13.3 1.5 2.1 14.2 menfc average 13.9 15.1 L.S.D. 5# - 0.6 1# - 0.9 rnTnn(iri3on of seasonal averages of all orchards and treatments: Qk 19^4-9» 1950 and 1951 9 and by the averages for the five orchards during the four years, which were: ferbam 13*9 percent, fixed copper 15®1 percent and nabam llj-*2 percent (Table 23). Effects of orchard management: The average percent soluble solids of all fruits from Orchard D during the four harvest seasons was from 2*2 to 2.9 percent higher than the fruit of the other orchards (Table 2L|.)« This difference may have been the result of delayed harvest, because the detailed study at East Lansing showed that percent soluble solids increased throughout the harvest season and increased most rapidly during the first two weeks of harvest* Effects of seasonal variation: The yearly average soluble solids content of all fruits from the five commer­ cial orchards did not change significantly in 19i+9, 1950 and 1951 9 however, in 1952 there was a significant decrease, from ll+.ij- percent in 1951 to 13®3 percent in 1952 (Table 23). This decrease was probably due to a higher moisture content of the fruit in 1952 as a result of the excessive rainfall occurring in July, 1952, which has been pointed out previously# 85 TABLE 2l|. THE INFLUENCE OF SEASONAL AND ORCHARD VARIATIONS ON THE AVERAGE SOLUBLE SOLIDS CONTENT (PERCENT) OF SOUR CHERHZ FRUITS FROM FERBAM, FIXED COPPER AND NABAM SPRAY TREATMENTS Orchard Season A B C E D L.S.D. between orchard averages within ia season % 1% 1 3 .0 0 .8 1 .0 11+..l|. 0 .6 0 .8 19lj-9 15.7 114-.6 13.7 1950 li|-.6 14.i+ 13.9 1951 H 4..O 1^.3 12.7 15.9 1 5 .0 1 .0 I.I4- 1952 12.7 13.3 13.7 1 3 .6 12.9 1.5 2 .0 lk o 2 13.5 1 6 .14. 1 3 .6 Average 1 ^ . 2 L.S.D. 5# - 1 .5; O 0 CD 17.1 vjt - 2.1 L.S.D. between seasonal averages within an orchard; 5$ 0 .8 1 .0 1 .14. 1.7 1 *0 1% 1 .2 1 .5 2 .2 2.5 1.5 DISCUSSION The cherry growers of Michigan are Interested in spray chemicals from the standpoint of: (1 ) their effectiveness to control pests, (2 ) their effect on size and weight of individual fruits, (3 ) total yield of fruit, (I4.) their accumulative effects on the productiveness of the trees over a period of years, and (5 ) the economy of purchase. This interest has prompted the search for new fungicides owing to the fact that numerous investigators have shown that the use of spray chemicals such as Bordeaux mixture and proprietory fixed copper compounds have caused dwarf­ ing of fruit and leaves and have reduced yields of fruit (6, 8 , 14, 20, 21, 24, 30, 36 ). Fruit processors, on the other hand, are vitally interested in spray chemicals as they affect the quality of processed fruit, and especially as they affect the soluble solids content of fruit. The soluble solids con­ tent of the fruit has been reported to be related to drained weight (20, 23)* Bedford and Robertson (1). However this was not found by Danger and Fisher (20) reported a definite decrease in soluble solids and total solids from the use of ferbam as compared to the use of fixed copper for the control of leaf spot. They stated also that, with a constant put-in weight of 85 ounces per No. 10 87 can, without exception the drained weight of processed cherries from trees sprayed with ferbam was lower than the drained weight of processed cherries from trees sprayed with fixed copper. Lewis and Groves (23) stated that 11a variation in soluble solids content from II4. to 18 percent may mean a difference of 11,500 No. 10 cans of cherries that can be obtained from a million pounds of fresh fruit.” If this is true, although contrary to the findings of Bedford and Robertson (1) who reported on the results from processing cherries from the different spray plots of the commercial orchards reported herein, the fungicides favorable to the processor could be somewhat unfavorable economically to the grower. The time of harvest as it affected maturity of fruits did not apparently change the weight or size of fruit except during the first three :to seven days after the fruits could be harvested commercially in the study carried on at the Michigan State College Horticulture Farm. A comparison of results from Orchard C with those of Orchard D in 191+9 and 1950 seems to verify these findings. Orchard D was located farther south than Orchard C, blossomed several days earlier than Orchard C and was harvested seven to ten days later than Orchard C. Yet, there was little to no difference between the weights of cherry fruits of these two orchards (Table 9)* These two orchards were similar in vigor, in soil management practices and general tree conditions. The occurrence of rain such as the 10-day 88 rainy period from July II4. to July 2 3* 1952, at the Michigan State College Horticulture Farm caused a significant in­ crease in the weight of fruit which was probably due to an increased water content* Fisher (11) and McMunn (26) reported similar increases in weight during rainy periods, and suggested that the increase in weight was probably due largely to reduced transpiration during periods of high relative humidity® However, when moisture was ample, excessive rains did not appear to increase the weight of fruit s * The time of harvest had little if any effect on the relation of fruit size and weight to spray materials at the Michigan State College Farm. Trees from the spray treatments which produced the largest fruits early in the season continued to have the largest fruits throughout the season (Tables 1 and 9) with no apparent change in size. This was shown also by comparing Orchard C and Orchard D in 19^4-9 and 1952. Lewis and Groves (21) found that the soluble solids content of cherry fruits increased significantly during the first two weeks of harvest. This finding appeared to be verified by the higher soluble solids content of fruits from Orchard D as compared to those from Orchard C. It has already been stated that Orchard X) blossomed earlier and was picked later than Orchard C. This was clearly demonstrated in the study made in East Lansing. The in­ crease of soluble solids content, as the picking season 89 progressed, was accompanied by an Increase In total solids content, an increase In total sugar content, and an increase in specific gravity which indicated a prolonged ripening process of the sour cherry fruits# Also, the occurrence of rain during the prolonged harvest peri od in 1 9 5 2 caused a leveling off of the foregoing increases. Lewis and Groves (21) reported a similar happening for soluble solids content of fruits. The effect of the increased rainfall was generally more pronounced in certain of the commercial orchards which was shown by the definite decrease of soluble solids con­ tent of the fruits in 1952 (Table 214-)# The season of 1952 was one of high rainfall compared to the three previous years# The 10-day rainy period at the Michigan State College Farm did cause a significant decrease of sugar content and increase of weight of fruits (Tables 1 and 7)o These changes were probably due to increases of water con­ tent of the fruit# Fisher (11) and McMunn (26) reported similar findings of cherry fruits during periods of rain­ fall and high relative humidity. The greater decrease of sugar content as compared to the decrease in soluble solids content during the rainy periods in 1 9 5 2 might be related, to the more favorable environmental conditions for vege­ tative growth and to greater enzymatic activity in assim­ ilating the sugars into higher carbohydrate compounds. The study at the Michigan State College Horticulture Farm, East Lansing, revealed that the weight of sour cherry 90 fruits was reduced by the use of fixed copper sprays below those from trees sprayed w ith ferbam (Table 10) • This agreed with the reports of other workers (6 , 8 , llj., 2 0 , 21, 2ii., 3 0 , 3^>) • However, the study made in five commercial orchards showed that the effect of fixed copper sprays on the weight of cherries was greater in some seasons than others* This conforms with previous reports (9, 31 9 37)* Trees injured by cold as in Orchard G during the winter of 1 9 5 0 - 1 9 5 1 were more severely affected by fixed copper sprays the following season than when sprayed with ferbam or nabam (Table l^A)o Studies conducted at East Lansing showed that during dry seasons the fruits from trees sprayed with copper were more severely affected than fruits from trees sprayed with organic chemicals (Table 10) • In seasons when rainfall was not abundant as in 191+-9 in the commercial Orchards A, B, and C, the soluble solids content of the fruit was significantly higher than in the fruits sprayed with ferbam or nabam (Tables 13B, li^B, and 15b) . The differences in results of the study made in the Michigan State College Horticultural Farm, East Lansing, In 195l and 19$2 and those made in the commercial orchards during the same years may be explained by the differences in tree vigor and seasonal rainfall in the two areas of the State# The trees on the Michigan State College Farm were very low In vigor, due primarily to the fact that they were growing in sod and had received no fertilizer, and both 91 seasons of fruit development, 1 9 5 1 and 1 9 5 2 , were very dry* By contrast, in the commercial orchards the trees generally were vigorous and the rainfall during all four years of the study, 1 9 l±9 through 1 9 5 2 , was adequate for good fruit development* This accounts for the fact that the fruits from the commercial orchards were heavier and were lower in soluble solids content than those from the East Lansing orchard* The effects of vigor of the trees and available moisture on the weight of fruits were clearly shown by the fact that the average fruit weight at East Lansing, expressed as the number of fruits per grams was 1 5 5 fruits for the East Lansing orchard compared to 115 fruits for the commercial orchards* Also in the commercial orchards fruits from the fixed copper spray treatments were often as heavy or heavier than those from the organic spray treatments, ferbam and nabam (Tables 13A through 17A)* The soluble solids content of fruits was used in this study as an indication of the composition of sour cherry fruits* This was found to be possible in view of the high correlations of soluble solids content with total solids content and with total sugar content (Figures IX - IV)« No previous reports of correlations of total solids, soluble solids and sugars of the sour cherry have come to the attention of the author. The soluble solids content was higher generally in fruits sprayed with fixed copper than in fruit sprayed with the organic materials in both the commercial orchards and 92 at East Lansing* This agreed with the reports of other workers (1, 2, 6, ll±., 19, 20, 21, 2 3 , 21+, 3 0 , 36, k, kh ). However, as was reported by Kenworthy and Mitchell (19), the average soluble solids content of fruits was influenced by variations in tree vigor and in seasons* Xn this study the effect of fixed copper spray treatments on soluble solids content was clearly shown to be influenced by tree vigor (Tables 13B and 17B)* and by seasonal variations (Table 23) • Xn Table 13B the use of the sod plus mulch type of soil management in 19i+9 in Orchard A resulted in trees that were lower in vigor than when the sod was re­ placed by clean cultivation* Also, trees low in vigor owing to cold injury produced fruit higher in soluble solids than in the years 1951 and 1952 before the cold injury occurred (Table l5B)* However, copper-sprayed fruits were, generally, higher in soluble solids content than fruits from the same environment sprayed with organic chemicals even though the number of fruits per was similar for all treatments* \\S K grams This disputed the common thought that larger fruits are always lower in soluble solids content than smaller fruits* Xn the study made at the Michigan State College Farm Orchard, East Lansing, fruits sprayed with lead arsenate were found to be higher in soluble solids and were lighter in weight than fruits sprayed with parathion* Fixed copper combined with lead arsenate definitely increased the soluble solids content and slightly decreased the weight of the 93 fruit when compared with fruits sprayed with ferbam plus parathion (Tables 11 and 12) ♦ A possible explanation of the injurious effect of fixed copper on the development of sour cherries may be associated with an inhibitory effect of soluble salts on amylase activity* According to Gortner (13) and Meyer and Anderson (27) even very minute concentrations of the soluble salts of copper may inhibit amylase activity, and this may interfere with the translocation of carbohydrates from the leaves to various parts of the plant* Vegetative growth would be limited because of the reduction in the quantity of carbohydrates translocated, which might reduce the development of new absorbing areas of the root system, thus limiting the amount of water that may be absorbed® McMunn (26) reported diurnal changes in water content of sour cherry fruits, and stated that it was due probably to a rate of transpiration in excess of the absorptive capa­ city of the root system and the transfer of water from the fruits to the leaves* Therefore, it might be conceiv­ able that a reduced carbohydrate supply, through the inhibition of amylase by soluble salts of copper, might reduce root absorption below the demands of transpiration, especially during periods of low relative humidity* A possible explanation of the effects of lead arsenate on the soluble solids content of cherry fruits might be the inhibiting action of arsenicals on growth substances* Bonner (3) has reported that arsenate inhibited the IAA- 9k induced growth of excised Avena coleoptiles through the inhibition of phosphate metabolism. Assuming this to be true in sour cherries, the increase in soluble solids of the fruit might be a result of accumulations of carbohy­ drates due to decreased vegetative growth* Prom the foregoing discussion and the data presented it may be concluded that fixed copper sprays used on sour cherries may reduce the weight of fruit and increase the soluble solids content, total solids content and total sugar content of the fruits when compared with fruits sprayed with ferbam and nabam. However, the physiological effects of any pesticide chemical on the quality of sour cherries may be modified to a great extent by the influences of variation in growing season and by differences of tree vigor* Also, differences in weight and soluble solids content of cherry fruits may be as great or greater between orchards or between harvest seasons than between spray treatments in any one orchard for any one growing saason* SUMMARY An investigation was made in 1951 and 1952 at the Michigan State College Horticultural Farm, East Lansing, to determine the effects of time of harvest on the pro­ gressive physical and chemical changes in the development of Montmorency cherry fruits (Primus cerasus L*) during a three-week harvesting period* Four trees were selected from a planting of 6l\. trees for uniformity of size and vigor* Approximately 600 grams of fruit were harvested bi-weekly from each tree for analysis as follows: fruit weight - determination of number of fruits required for grams; size of fruit - average transverse diameter of 20 fruits; firmness of flesh - determination of percent compression in direction of transverse diameter; soluble solids content - refractive indices of expressed juice; total solids content - average oven dry weight of entire fruits; total sugar content - percent invert sugar deter­ mined by the Munsen Walker gravimetric procedure; specific gravity - calculated from weight of fruit in air and when submerged in water* 1* There was a significant increase in soluble solids, total solids, and total sugar content and in specific gravity of the fruits as the harvest progressed* The most pronounced increase was during the first two weeks of the 96 harvesting period. Highly significant positive correla­ tions were found between increases in soluble solids and total solids in 1 9 5 1 (r = 0 .8 l 6 ), and 1 9 5 2 (r = 0 .9 6 6 ) and between the increase in soluble solids and total sugar in 1952 (r — 0 .9 2 3 ), as the harvest season progressed. 2. A decrease in the total solids content of the fruit was noted in all treatments immediately following a 1.27-inch rain on July 27 9 1951* A similar decrease in total sugar and increase in weight of fruit were noted in all treatments following a 10-day rainy period, from July II4. to July 23» 1952, during which time lo93 inches of rain fell. 3* The fruits became gradually less firm for two weeks following the beginning of harvest, after which time they became more firm. I}.. The average transverse diameter of the cherries changed very little throughout the harvest period. A second study was made in 1951 and 1952 at the Michigan State College Horticultural Farm, East Lansing, to determine the effects of certain inorganic and organic spray chemicals on the weight and soluble solids content of sour cherry fruits. 1. Trees sprayed with fixed copper produced fruits higher in soluble solids content and lower in weight than fruits sprayed with ferbam. 2. Fruits from trees sprayed with lead arsenate tended to be lower in weight and higher in soluble solids content 97 than those from trees sprayed with parathion* Trees sprayed with fixed copper plus lead arsenate definitely produced fruits lower in weight and higher in soluble solids than trees sprayed with ferbam plus parathion# 3« There was evidence that the dry weather during the 1952 harvest season had a greater influence than spray treatments on the weight of cherry fruits# A third investigation was made from 19^-9 to 1952, in five commercial orchards located in two of the cherry producing areas of Michigan, to determine the effects of spray materials, variations in orchards, and variations in seasons on the weight and soluble solids content of Mont­ morency cherry fruits* The fungicidal spray materials used in this study were ferbam, fixed copper, and nabam. The sprays were applied by the grower as a part of his regular spraying program. Samples of fruit were collected in each orchard at the same time the grower was harvesting the crop# 1# Trees of moderate vigor, sprayed with fixed copper produced fruits lighter in weight during 1914-9 than trees sprayed with ferbam or nabam* However, trees of very high vigor, sprayed with fixed copper, produced as heavy or heavier fruits than trees sprayed with ferbam or nabam* This was especially true in years when rainfall was high during July just before harvest. There was generally no difference between the weight of fruits sprayed with ferbam and nabam# 2# Even though trees sprayed with fixed copper pro- 98 duced fruits with, lower soluble solids content than those sprayed with ferbam or nabam, differences in soluble solids content of fruits from different orchards and in different seasons were as great or greater than the differences due to spray materials* 3* Xn Orchard C, low tree vigor caused by winter injury resulted in increased soluble solids content and reduced weight of fruits from all spray treatments* How­ ever, the use of fixed copper had a greater unfavorable influence on number of fruits per grams (weight of fruits) than did nabam and ferbam, and a more favorable influence on the soluble solids content than nabam and ferbam* 14-* Xn Orchard A changing soil management from sod to clean cultivation resulted in a significant decrease in soluble solids content of harvested fruit from all spray treatments and significantly increased the number of fruits per grams (weight of fruits) harvested from all three spray treatments* LITERATURE CITED Bedford, C. L* and W. F. Robertson* 1953* Effect of spray materials on the quality of canned and frozen Montmorency cherries* Food Tech* 7(3) s1,J|2-1 Vl * Blodgett, E* C* and R* 0* Magie. 1936* progress of studies of the epidemiology and control of cherry leaf spot* Phytopath* 26:97* Bonner, James* 1950* Arsenate as a selective inhibitor of growth substance action* Plant Pathology 25(1): I8I-I8I4.* Bullock, R* M* 1952* A study of some inorganic com­ pounds and growth promoting chemicals in relation to fruit cracking of Bing cherries at maturity* Proc* Amer* Soc* Hort. Sci. 5 9 :214-3 -2 5 3 * Caldwell, Joseph S. 1934-* Hydrion concentration changes in relation to growth and ripening in fruits* U. S* Dept* Agr. Tech* Bull* lj.03:l-5q* Cation, Donald and E* J. Rasmussen. 1937* Comparisons of some old and new materials for spraying cherries* Mich* Agr* Exp. Sta. Quart. Bull* 19(3)21-20* Daines, Robert H* 1939® Two year experiments in the control of cherry leaf spot (Coccomyces hiemails )* Phytopath* 29:5* Dutton, ¥• C* and H* M* Wells. logical effects of Bordeaux. Hort. Sci. 21:277-281. 1923* Some physio­ Proc, Amer. Soc* ____________ ♦ 1925* Cherry leafspot• Mich. Agr. Exp. S t a • Spec. Bull. 147 21-13* and L. R. Parish. 1935* Comparisons of high-calcium and dolomitic hydrated limes in Bordeaux, zinc-lime and iron-1ime on cherry and peach. Proc. Amer. Soc. Hort. Sci. 332186-190* Fisher, D. F. 1922. Effect of alkaline sprays on the size of sweet cherries. phytopath. 12:10i4-* 100 12 • Fisher, Vernon J • 1950. The effect of various foliar sprays on the size and composition of the fruit and on the rate of respiration of the leaves of the red cherry (Prunus cerasus L*)* Unpublished Ph.D. thesis, Michigan State College. 92 pp. 13. Gortner, Ross A. 191+9. Outlines of biochemistry, 3rd ed. New York: John Wiley and Sons, Inc. 1078 pp. IJ+O Groves, A. B., H. J. Miller and C. F. Taylor. 191+3* Tri-state cherry-spray investigations. West Virginia Agr. Exp. Sta. Bull. 310:1-26. 15 . Juritz, C. F. 1925. Effects of spraying citrus trees on the composition and flavour of the fruit. Union of South Africa Dept. Agr* Jour. 11:21+0-21+3. 16* Johnson, Erik M., A* L. Kenworthy and A. E. Mitchell. 1950. Influence of spray materials on the structure of sour cherry leaves (Prunus cerasus L. var. M o n t ­ morency) . Proc. Amer. Soc. Hort. Sci. 55:195-198. 17. Keitt, G. W • 1918. Third progress report on investi­ gations of leaf spot of cherries and plums in Wisconsin* Phytopath. 8*72. 18. ______ an