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Effect of varying levels of nitrogen, phosphorous, potassium, and calcium on the quality of the Newburgh… Enns, Peter Bernhard 1949

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L £ 5 7 Co-p • I The Effect of Varying Levels of Nitrogen, Phosphorus, Potassium, and Calcium on the Quality of the Newfcurgh Raspberry Peter B. Enns A Thesis submitted in Partial Fulfilment of the Requirements for the Degree of Master of Science in Agriculture in the Department of Horticulture (Plant Nutrition) Approved: (Ma j or) (Minor) The University of British Columbia April, 1949 ACKNOWLEDGMENTS The writer gratefully acknowledges the assistance and kind criticisms of Dr. G. Howell Harris, Professor of Horticulture, under whose guidance this project was carried out* Acknowledgment is extended to Br. A.F. Barss, Head of the Department of Horticulture, for the kindly interest shown, and to Miss Jean McMullan, instructor, Department of Horticulture, for her helpful suggestions in laboratory technique,, Thanks are also tendered to Mr. G.J. Derksen, on whose field the experiment was carried out, to the Yarrow Growers Cooper-ative Association, who supplied the fertilizer, to the Sumas Coop-erative Association, for supplying freezing and storage fac i l i t i e s , and to Western Canners of Mission City, for processing the canned sampleSo c TABLE OF CONTENTS Page 1* Introduction • 1 2 . Review of literature 3 3 . Materials and Methods 4 (a) location and layout of experiment L (b) Preliminary soil analysis and results • 7 (c) Fertilizers used and method of application ......... 8 (d) Method of harvesting and processing of berries 1 0 (e) Methods of analysis of fruit 10 4* Observations and results 12 5. Discussion of results 34 6. Summary and conclusions .C . A . ^ 7 £ £ £ . " 0 38 7. Literature cited 39 1 INTRODUCTION The Newburgh raspberry, ever since its development at the New York State Experiment Station, Geneva, New York, has been noted for its superior vigor and productiveness, and its ability to withstand winter in-jury even in areas in which, a high water table is common. In many dist-ricts of the Fraser Valley,in which restricted sub-surface drainage is prevalent,the variety was received enthusiastically largely because of these qualities. During the period of World War 11 and the immediate postwar years there was an increasing market for sulphur dioxide preserved berries to supply the overseas demand. Since a ready market awaited a l l the fruit that could be produced, yield became of paramount importance, and' quality received l i t t l e attention* Under these circumstances the Newburgh became the dominant var-iety in the new plantings. In some of the newer districts of Sumas Prairie, Yarrow and Chilliwack, this variety accounted for as high as 90$ of the total raspberry acreage. With the termination of the overseas contract in 1945» the mar-ket for sulphur dioxide preserved berries was virtually wiped out, leaving the berry industry dependent largely on local and American markets for the fresh and frozen product. This situation brought the weakness of the Newburgh into the limelight. Its low sugar content, resulting in a rather acid flavor, be-gan to draw increasing criticism. Likewise its adaptability for the quick freeze method of preserving became rather doubtful. A product is said to 2 possess freezing qualities to the extent that it retains, during and af-ter freezing, its natural shape, colour and flavor. Due to its high water content, the Newburgh does not retain its shape very well. Its relatively low sugar content often results in too tart a flavor, or, i f acidity also is lacking, gives i t a flat taste. Since the Newburgh possesses characteristics which make i t par-ticularly suited to certain areas, the question arose, whether fertilizer treatments could be used to improve its quality. Considerable work has been done in the past on the effect of fertilizer treatment on plant growth, general vigor and yield. Not until quite recently, however, has any att-ention been given to its effect on the quality of the crop produced. The purpose of the present experiment was to ascertain the ef-fect of varying amounts of nitrogen, phosphorous and potassium in the fer-t i l i z e r applied on the quality of the Newburgh raspberry. Determinations were made on sugar content, vitamin C. content, total solids, soluble solids, proteins, acidity, total minerals, flavor, and freezing quality, a l l of which are important characteristics of quality. 3 REVIEW OF LITERATURE Food quality studies are Of relatively recent origin. The char-acteristics most commonly dealt with in such studies are sugar content, vitamin content and acidity, either total or active. The work done to date on the effect of various fertilizer materials on these characteristics of quality, indicates that the level of nitrogen fertilizer applied is invers-ely correlated with both sugar and Vitamin Content. Phosphate fertilizers have been shown to have an influence on the flavor of the fruit produced. Thus Darrow (6) found that plants which had received superphosphates to-gether with nitrogen fertilizer produced much sweeter and better flavored berries than plants receiving no phosphates. Similar results were obtain-ed by Yercier (29). Reed (22) observed that the absence of phosphorus gr-eatly impaired the transformation of starch into water-soluble carbohy-drates. The effect of potasium fertilizer on the sugar content of plants has been investigated by numerous workers, but the results are very con-tradictory and confusing (19). Regarding the effect of potash on flavor Darrow (6) and Vercier (29) found that strawberry plants fertilized with sulphate of potash or muriate of potash produced berries that were sour and lacked flavor in comparison to berries from plants receiving the nitro-gen plus superphosphate treatment. That sugar content and total acidity are closely connected with flavor was demonstrated by Harding and Wadley (10) who found high correla-tions between palatability and both total acids and solids. Currence and Larson (5) also showed a significant correlation between quality score and refTactometer readings. Bartholomew and Sinclair (4) found a high corre-lation between total soluble solids and total sugars in orange juice. In a later paper (24) the same authors point out that "in fruit-quality stud-ies, the proportion of total sugars to total soluble solids, not the absol-ute amount of total soluble solids, is the factor which primarily affects the sensation of sweetness". The fact that in most fruits the total sug-ars make up the major portion of tha total soluble solids accounts for the close correlation between total soluble solids and edible quality. MATERIALS AND METHODS (a) location and Layout of Experiment The location chosen for the experiment was a field of four year old Newburgh raspberry plants at Yarrow, B.C. This district was chosen be-cause of the proportionately large acreage devoted to the Newburgh variety. A field experiment consisting of four adjacent blocks; of ten plots each was laid out according to the randomized block system. The ex-act layout is illustrated in figure (l) and (2). The rows were 8 feet wide and the plants in the rows 3 feet apart. Each block consisted of five rows. Of these five rows numbers 1,3 and 5 served as buffers. In the even-num-bered rows the two plants at each end as well as every tenth plant also ac-ted as buffers. Each plot, therefore, consisted of nine plants and was in area 27 feet by 8 feet - 216 square feet or approximately one-two hundredth of an aore. For fertilizing purposes, however, the size of plot became 30 feet by 16 feet - 480 square feet or approximately one-nlntieth of an acre. This difference i s due to the fact that the fertilizer was applied broad-cast, so that the buffer rows on either side as well as the buffer plants at each end of the plot received an equal share of fertilizer. This dif f -ence in plot size is illustrated in figure (3). 4a ROWS I 7 t 1 \ 1 0 + I 8 I 1 T C 5 I r 1 0 X A t i 1 10x 7 I D I a i 9x 1 7 1 ID 1 B 2 3 a BLOCKS A - D I 9 I t a i TREATMENTS — 1 - lOx f i g . 1 . Layout of Blocks and Plots (x—Buffer plants) 5 6 N 2 P 2 Kj 3 N2 P2 K1 + L i m ® 10X Check 3 N2 P2 K l + I l m € 7 N^K^ + Lime 5 V 2 V L i m ° N P K J Lime 2 2 a 6 N P K .2 2 2 1 N P K -f Lime 12 1 9X Milorganite 2 N P K 2 2 1 8 N P K f Lime 3 2 3' 2 N„ P„ K, 2 2 1 N P K i Lime j 4. X. 5 N1 P2 K3 + U m e 9 Milorganite + Lime 10 Check + Lime 8 N P K 4 Lime 3 2 3 T U N P K 4 Lime 3 2 1 1 1 N P K 4 Lime 12 1 5 N1 P2 K3 4 L i m e 10X Check 6 2 2 3 3 NPK 4 Lime 2 2 1 3 4 Lime 9 Milorganite + Lime 1 N P K + Lim« *C J. U NPK 4 Ume 3 2 1 .2 N P K 2 2 1 7 N P K 4 Lime 2 2 2 9X Milorganite 5 N P K 4 Lime 1 <c 3 & N P K 4Lime 3 2 3 6 N2 P2 S 2 N P„ K 2 2 1 N P K 4 Lime 3 2 1 T 1 NP K 4Lime 1 2 1 10 Check + Lime , " I 8 N P K 4 Lime 3 2 3 Randomized plots with respective treatments Legend: N l = 2 0 lbs/Ac(low) N 2 - 60 lbs/Ac (Med) N3= 160 lbs/ac.(high) P 2 = SO lbs/Ac Ki - 30 lbs/Ac (Low) K3- 90 lbs/Ac.(high) Milorganite: 1 Ton per Acre Lime 1 Ton per Acre \ 6 * X 3ti x X X 96 X X x :: o o o o o o o o • o I J * X X X X X X X X ss-Legend: Boundary of plot fo r f e r t i l i z i n g purposes. Area: 30 feet by 16 feet equals 480 square? feet, Boundary of p lo t for ca lcu la t ing y i e l d . Area: 27 feet by 8 feet equals 216 square fee t . o x Plants from which berr ies were harvested. Buffer p l an t s . f ig .(3) A representative plot showing buffer plants and plants from which berr ies were harvested. Nature of soil and Method of Analysis The soil on which the experiment was located is classified by the Lower Fraser Valley Soil Survey (25) as a Monroe Clay Loam* It is gener-ally of a highly fertile nature and except for its restricted sub-drainage is well adapted to the growing of cane fruits* Although a detailed analysis of the soil was not carried out, an attempt was made to determine the relative level of f e r t i l i t y of the soil on which the test plots were located* Soil samples were taken on February 21, 1948, and analyzed at the Plant Nutrition laboratory, U.B.C., for nitrogen phosphorus, potassium, magnesium, organic matter, and soil reaction. The methods outlined by Morgan (20) were used in making a l l determinations except that of soil re-action* The latter was determined with a Beckman pH meter, using a glass electrode* The results of the preliminary soil analysis are given in Table 1, below* They indicate that both nitrogen and potassium content were very low* . This is in agreement with the findings of Harris and Woods (12) in Table (1) Results of Preliminary Soil Analysis Sample No. N. P. K. Mg. Organic Matter pH 1 very low low med. very low high high 5.85 2 « med. n n 11 5.25 3 11 low med. i t i t 5*1 4 t t low med* n i t » 5.35 5 i t med. t i n n 5.05 6 n low med. i t t i - i t 5.25 composite sample 5*35 6 t h e i r work on the seasonal v a r i a t i o n of plant nutr ients i n raspberry p lan t -ings of the Fraser Y a l l e y . The phosphorus content ranged from low to med-ium and the magnesium content was high* Organic matter was h igh i n a l l sam-ples tested* The s o i l samples var ied considerably i n a c i d i t y wi th pH v a l -ues ranging from 5*05 to 5*85* A composite sample comprised of equal am-ounts of a l l samples gave a pH reading of 5*35 which i s sa t i s fac tory for the growing of raspberries on a s o i l of t h i s type. However, i n order to ascer ta in whether l iming had any effect on the qua l i t y of the f r u i t lime was applied at the rate of 1 ton per acre , or 22 lbs* per p l o t . As immediate or f i r s t - y e a r effects were desired the Ca (OH)2 form, sold commercially as a g r i c u l t u r a l l i m e , was used. The am-ount appl ied i s , t h e o r e t i c a l l y , enough to r a i se the react ion of a c l ay loam, high i n organic matter, such as was used i n t h i s experiment, approximately 7 u n i t s . The lime was broadcast by hand on March 19, 1948. (c) F e r t i l i z e r s used and method of app l i ca t ion The f e r t i l i z e r materials used were ammonium sulphate (20-0-0), superphosphate (0-18-0), and muriate of potash (0-0-60). Also included was a treatment using an organic f e r t i l i z e r , so ld commercially as M i l o r g a n i t e . The l a t t e r treatment was included since t h i s f e r t i l i z e r was being used ex* t ens ive ly i n the Yarrow d i s t r i c t . The rates at which the f e r t i l i z e r s were appl ied i n the various treatments are given i n table (2). The fact that raspberries respond w e l l to luxurious phosphorus feeding was noted by Har r i s ( l l ) and l a t e r confirmed by Hornby (14). In order to keep the number of treatments as low as poss ib le , only one l e v e l of phosphorus, 80 l b s . per acre , was used. This i s w e l l above the average l e v e l usua l ly recommended for raspberries i n that d i s t r i c t . 9' TABLE (2) Fertilizer Treatments as applied to Newburgh Raspberry-Plots . . TREATMENT NO. . N . P n 0 C K„ 0 lbs./acre lbs./acre lbs./acre 1 < W l > 20 80 30 2 X ( N 2 P 2 V 60 80 30 3 ( N 2 p 2 y 60 80 30 4 ( N 3 P 2 V 160 80 30 5 < Y a V 20 80 90 6 X ( N P K ) 60 80 90 7 60 80 90 8 160 80 90 9 (Milorganite) 120 40 0 9 X (Milorganite) 120 40 0 10 (Check) 0 0 0 10 X (Check) 0 0 0 # - 1 - low; 2 - medium; 3 ~ high X - Treatments marked X did not receive any lime. A l l others received lime at the rate of 1 ton per acre. (d) Method of Harvesting and Processing of Berries The samples for analysis were harvested and processed as indica-ted in Table (3). The berries were picked directly into 20 oz. tins to a-void unnecessary handling* To ensure as representative a sample as poss-ible, four or five berries were picked from both sides of each plant in the plot. The samples for canning were taken into cold storage and canned the same day. Aside from the fact that no syrup or sugar was added, the reg-ular commercial canning procedure for canning raspberries was used. This consisted of a twelve minute exhaust period at 18$°F. followed by an 8 minute cook at 210°F. in a continuous rotating cooker. The samples were then cooled in a water bath and stored at room temperature in the Plant Nutrition laboratory, Department of Horticulture, U.B.C. The frozen samp-les were stored at the Abbotsford cold storage plant until the beginning of November and were then transferred to the freezing unit of the Animal Pathology Department, U.B.C, and held at 0°F. until opened for analyses. Table (3) Dates of Harvesting, and Methods of Preservation - of Newburgh Raspberries  Picking Date # Method of Preser- Code No. of vation Series July 17, 1948 Canned C - 1 July 24, 194* Frozen F - 1 July 31, 1948 Frozen F - 2 July 31, 1948 Canned C - 2 # One sample per plot was picked on each picking date (e) Methods of Analysis of Fruit The determinations made in the laboratory included, Vitamin C, total solids, total soluble solids, total sugars, total acidity, total min-erals, proteins, flavor and freezing quality. (i) Method of Vitamin C_. Determination The method used here was the Indophenol-xylene Extraction Method for Ascorbic Acid used by Robinson and Stotz (23). The modification for interfering substances was found to be unnecessary and therefore the basic method was used. (ii) Total solids were determined by drying a 25 gm. sample of fresh weight in a drying oven for seventy two to ninety six hours at 60°C. A l l determinations were made in duplicate. ( i i i ) Total soluble solids were estimated by use of a Bellingham and Stanley refractometer graduated to read in percentage of sugar. (iv) Total sugars were determined according to the method of the Ass-ociation of Official Agricultural Chemists (2), using 20 grams of juice. (v) Total acidity - This was also determined according to the method of the Association of Official Agricultural Chemists (2). (vi) Total Minerals- determined on a one gram sample of oven dry mater-i a l . A muffle furnace was used with a temperature of 600°F. A l l samples were ashed in triplicate. (vii) Flavor and freezing quality were determined by a tasting panel comprised of four smokers and four non-amokers. The method used in grad-ing edible quality was used by J.D. Winter (31) in his work on "Strawberry and Raspberry Varieties for Freezing Storage". The scoring system was mod-ified to the extent that color was rated twice as important and flavor three times as important as the other two characteristics, texture and sh-ape. This modification was considered to be more appropriate since only one variety was concerned in which ease both color and flavor were deemed more important than either texture or shape. (viii) Protein Content was determined according to the method of the Association of Official Agriculture Chemists (2). 12 OBSERVATIONS AND RESULTS Field Observations on General conditions of Plants  as observed on Dates of Harvesting In spite of the extremely wet growing season and flood condi-tions only two plots, 0£, and Cy, showed marked effects of excess moisture. The two plots were situated in a slight depression at the extreme end of the field (see f i g . 1 . ) . The plants in both plots were stunted badly and the foliage was a greenish yellow as might be found in a case of extreme nit rogen deficiency. Although no definite symptoms of nitrogen deficiency were not-iced except in the two above mentioned cases, every plot conspicuous for its somewhat sparse foliage was found to be of Treatment 1 (lowN.) Treat-ment 5 (lowN.) or the Check Plots 10 and lOx, both of which had no Nitro-gen. Likewise, the few plots which were outstanding because of their lux-uriant growth were invariably of the high Nitrogen treatments. Plants bearing uniformly large berries were much more prevalent in the plots receiving medium or high nitrogen than in plots to which low nitrogen or none at a l l had been applied. Vitamin C Results of the analyses for vitamin C are given in Table IV, v, and VI. Statistical analyses, Table V., showed that the fruit from un-limed plots had a significantly higher Vitamin C content than fruit from plots that had received lime. Varying nitrogen levels in the fertilizer treatments had no significant effect, although there was a trend for the Vitamin C content to increase with increased nitrogen up to the medium level and then to decrease with the high nitrogen level. The depressing 13 effect of lime on the Vitamin C content tended to be minimized by a high level of potassium (Table VI). It will be noticed, for instance, that a l -though lime lowered the Vitamin C content in both the low and high potass-ium treatments, i t only lowered it by 31.00 - 29.23 B 1.77 mg« per 100 gm. at the high potassium level as against 31*22 - 27.8 • 3«42 mg. per 100 gm. at the low potassium level. amin C content of raspberries. It also serves to illustrate the fact that in fertilizer treatments high in potash (treatments 7 .and 8), the Vitamin C content is not lowered as severely as in treatments low in potash (treat-ments 1,4 and 10). Total Sugars The results from total sugar determinations on the complete F-l series are given in Table 711. Analyses of Variance (Table Vlll) indi-cate a significant difference between treatments. When the high nitrogen fertilizer treatments are compared with the low nitrogen treatments, the difference is found to be highly significant, i.e., the nitrogen level in the fertilizer treatment, and the sugar content of the raspberries prod-uced, appear to be negatively correlated. This negative correlation is illustrated in f i g . 5. Below are the results of the percentage sugar content from the various fertilizer treatments arranged in descending order: Fertilizer Treatment % Sugar Content Fertilizer Treatment-^ Sugar Figure 4 illustrates graphically the effect of lime on the vit-Content 2.92 2.86 2.77 2.75 2.72 2.72 2.62 Check 4 lime 2.60 N 2 P 2 K 3 "* l i m e 2.60 2.56 2.52 2.47 Check - lime Milorganite-Lime N2 P2 K1 * L i m e Milorganite^lime N j P ^ 4 lime N1 P2 K3 4 l i M 8 14 In order to determine whether any one treatment gave signifi-cantly higher results than another, the larger figure must be as great or greater than the sum of the smaller figure plus the significant differ-ence. Thus N 2 P 2 K 3 T lime (2,92) is greater than the N ^ B J K J - lime treatment (2.62) or any treatment below i t , Likewise i t can be said that the top four treatments are the only treatments which can be considered as giving a significantly higher sugar content than the Milorganite - lime treatment which gave the lowest results. Total Solids Table 1JC gives the percentage dry weights or total solids for both the F - l , (frozen) and 0-1 (canned) series. None of the three variab-les used in the fertilizer treatments i.e., nitrogen, potassium or lime, had a consistent or significant effect on the dry weight of the fruit. The only noteworthy feature in the table is the fact that plots C5X and C7, the only two plots which suffered markedly from excess moist-ure, produced fruit which was highest ±a total solids in both the frozen and canned series* Total Soluble Solids Table X gives the percentage of total soluble solids, as deter* mined by a refTactometer, of both F-l and C-l series of raspberries. Al-though the results were not analyzed statistically for significance, they were compared with both edible quality,Table X l l , as determined organolepti-cally by a panel of eight co-workers, and by total acidity (Table XL, F-2 series). The obvious correlation between total soluble solids and edible quality is shown in figure 6. The negative correlation between edible qual-ity and total acidity is also illustrated in figure 6, 15 Total Acidity The correlation between total acidity and edible quality has a l -ready been mentioned. Another interesting feature of the total acidity results in Table XL is illustrated in figure 7, where the average total acidity val-ues per treatment, of both F-l and F-2 series are plotted in ascending or-der. Possible reasons for the considerably lower values in the F-2 series will be discussed later* Edible Quality The results in Table X l l were derived by taking the average of the total score allotted to samples from each treatment for color, shape, texture and flavor. The points allotted for color were doubled, those for flavor were tripled, while those for shape and texture were left unaltered. The reason for weighting color and flavor was already mentioned. Total Minerals The percentage ash weights of fruit from both F-l and C-l ser-ies are given in Table X l l l . The analyses of variance Table XIV show that while there is no significant difference between individual treatments, there is a highly significant difference between the mineral content of raspberries from limed treatments and those receiving no lime. Figure 8 shows that a l l the limed treatments resulted in fruit which was lower in minerals than fruit from treatments receiving no lime. Protein Content Table XVI gives the protein content of the juice from Newburgh raspberries of the F-l series. Table X7111 shows the protein content of Newburgh raspberries including the seeds. Statistical analyses .Table X711 of the results in Table XVII indicate that the no one fertilizer treat-ment gave a significantly higher protein content than another treatment. 16 However, the averages of the high, medium, low Nitrogen treatments in the C-l series are, 1.149* 1»148 and 1.094 respectively, showing a tendency for Protein content of the fruit to increase with the level of Nitrogen applied in the fertilizer treatments. Conductivity The results given in Table XV". showed no consistent trends. 17-TABLE 1¥. Vitamin G Content of Nfewburg Raspberries from Plots Receiving Varying Amounts of Nitrogen, Phosphorus, Potassium and Lime Fertilizer Treatment s . A B C 13) Total Av. Mg. per 100 E l Juice 1 ( N ^ } 27.95 30.87 26.62 23.04 108.48 27.12 2X ( N ^ ) 30.27 28.80 24.53 24.84 108.44 27.11 3 ( N 2 P A ) 25.98 31.95 28.05 29.52 115.50 28.8V 4 ( N ^ ) 29.00 25.65 24.53 30.24 109.42 27.35 5 ( N P K ) 1 2 3 26.56 29.79 28.38 28.08 112.81 28.2 6X (NPK j 2 2 3 29.35 28.26 34.32 32.04 123.97 31.00 7 (N2P2K3) 28.65 29.79 32.23 27.72 118.39 29.6 8 ( i y a V 29.69 29.79 27.28 32.76 119.52 29.88 9 (Milorganite) 25.63 26.64 30.36 31.68 114.31 28.58 9X(Milorganitej 31.09 34.47 27.28 32.49 125.33 31.33 10 (Cheek) 29.23 23.58 30.14 25.56 108.51 27.13 10X( Check) 34.80 29.97 33.33 30.24 128.34 32.1 X - Treatments without lime. TABLE 7. Analyses of Variance of Vitamin C Content of Juice of . Raspberries Receiving Varying Amounts of Fertilizer  Degrees of Source of Variation S.3. freedom Variance Calculated F. Tabled F. 1.56 5.56 4.14(1- t .05) Total 400.32 47 8.51 Total Treatments 136.80 11 12.43 Limed vs. TJnlimed (44.31) (1) 44.31 Block .26 3 .09 Error 263.26. 33 7.97 TABLE 71. The Effect, of Nitrogen, Potassium, and Lime in Fertilizer Treatments on the 7itamin C Content (in mg. per 100 gm.) of Newburgh Raspberries. Fertilizer Treatment s: High Nitrogen Medium Nitrogen Low or Bo Nitrogen i Averages + Lime - Lime + Lime - Lime + Lime - Lime High Potassium + Lime 29.88 29.60 28.20 + Lime 29.23 29.87 High Potassium - Lime 0 31.00 .. o ! i 1 - Lime 31.00 Low or No Potassium + Lime 27.35 28.58 28.87 27.12 27.13 i i + Lime 27.80 28.92 Low or No Potassium - Lime 31.33 0 ! 32.10 i - Lime 31.22 Average + Lime 28.60 29.23 27.48 i • r i i j + Lime 28.44 Average - Lime 31.33 31.00 32.10 | i - Ii-me 30.83 29.28 29.82 28.64 19 o o u Pi 33 32 31 30 29 28 27 26 _ lOx I Uhlimed Treatments - / > ^ 9 / 2x _ — 1 10 ^ Limed Treatments fig.(4. The effect of lime on Yitamin C content 1 ( N x P 2 ^ ) 5 (Nx P 2 K3 ) 9 Milorganite 2x ( N F K } 6x (N P K ) 9x Milorganite 2 2 1 2 2 3, 3 ( N P K ) 7 (N P K ) 10 Check 2 2 1 2 2 3. L ( N 3 p 2 \ } 8 l N3 P2 K3 } 1 0 X C l i e C k x *- treatments without lime 20 TABLE H I . Total Sugar Content of Newburgh Raspberries from Plots Receiving Varying Amounts of Nitrogen, Phosphorus, Potassium and Lime Fertilizer BLOCKS Treatments A B C © Total Average Percent, of Fresh Weight * 1 ( N ^ ) 2.50 2.82 2.74 2.84 10.90 2.72 2 X ( N ^ ) 2.43 2.68 2.58 2.81 10.50 2.62 3 C V j f t ) 2.64 2.52 2.48 2.66 10.30 2.52 4 ( H ^ ) 2.45 2.61 2.46 2.90 10.40 2.60 5 ( H ^ ) 2.36 2.84 2.86 2.84 10.90 2.72 6x U ^ j 2.55 2.78 3.23 2.54 11.10 2.77 7 ( H ^ ) 2.76 2.88 3.26 2.80 11.70 2.92 2.50 2.63 2.60 2.67 10.40 2.60 9 (Milorganite) 2.45 2.50 2.45 2.50 9.90 2.47 9x(Milorganite) 2.50 2.62 2.50 2.62 10.24 2.56 10 (Check) 2.82 2.82 2.90 2.90 11.44 2.86 10x(Check) 2.72 2.78 2.72 2.78 11.00 2.75 x - Treatments without lime TABLE T i l l . Analyses of Variance of Total Sugar Content of Newburgh Raspberries from Plots Receiving Varying Amounts of Fertilizer Source of Variation S.S. Degrees of freedom Variance Calculated F. Tabled F. Total 1.99 & .0423 Total Treatments • .78 11 .0709 2.46 ;r 2.11(P= .05) 2.87(P= .01) Low Nitrogen vs. High Nitrogen (.35) (1) (.35) 12.15 Block .26 3 .087 3.02., Error .95 33 .0288 U Significant Difference between means • .26 21 CO 3 3.0 2.8 2.6 2.U 2.2 2.0 Low Nitrogen LOx 9x High Nitrogen fig.(5) Comparison between the effect of high nitrogen and low nitrogen fertilizer treatments on sugar content. 1 (Hx P 2 ^ ) 2x (N 2 P 2 1^ ) 3 ( N 2 P 2 K l ) 4 ^ 2 * 1 ) 5 ( H. P 2 K3 ) 6x ( N 2 P 2 K3 ) 7 ( N 2 P 2 ^ ) S ( N 3 P 2 K 3 ) 9 Milorganite 9x Milorganite 10 Check 10x Cheek x - treatments without lime 22 TABLK IX. Total Solids of Newburgh Raspberries from Plots Receiving Varying Amounts of Nitrogen, Phosphorus, Potassium and Lime F-l Series . Fertilizer BLOCKS Treatments. A B C JJ Average Percent of Fresh Weight 1 (NjPgKl ) 12.14 12.48 12.48 13.12 12.55 2x (N2JP2K1 ) 12.88 13.20 12.64 13.26 13.13 3 ( N 2 P 2 K L ) 12.48 12.36 12.68 13.19 12.68 4 ( N 3 P 2 K L ) 12.25 12.18 11.68 12.85 12.24 5 V2K3 ) 13.48 12.96 13.02 13.08 13.13 6 * { N2 P2 K3 } 7 ( ^ P ^ ) 12.28 12.46 14.28 12.42 12.86 12.24 12.61 13.04 12.58 12.62 8 (N 3 P 2K 3) 9 (Milorganite) 13.04 13.00 12.12 13.22 12.85 12.64 12.84 12.65 12.83 12.74 9x(Milorganite) 12.40 12.94 12.30 12.84 12.62 10 (Check) 12.32 12.68 12.36 12.72 12.52 10x( Check) 12.52 12.72 12.93 13.11 12.82 C-l Series Fertilizer Treatments. A BLOCKS B C Average 1 (NjPjft. ) 12.72 12.14 12.22 12.68 12.44 2x (N 2 P 2K 1 ) 12.53 13.26 12.38 12.40 12.64 3 (Hjftfi. ) 13.25 12.63 12.89 11.92 12.68 4 ( ^ 2 % ) ) 12.71 12.63 12.30 12.84 12.62 5 ( N1P2K3) 12.40 11.91 11.92 12.76 12.25 6x (N2P2K3 ) 12.75 12.57 14.60 11.66 12.89 7 (N2P2K3 ) II.85 12.07 14.08 12.72 12.68 8 (N3P2K3 ) 12.96 11.92 12.28 12.68 12.46 9 (Milorganite) 12.83 12.22 12.30 11.68 12.26 9x (Milorganite) 12.19 12.92 11.76 12.49 12.34 10 (Check) 12.32 12.06 12.76 12.50 12.41 10x(Check) 12.65 12.70 12.81 12.84 12.75 23 TABLE X. Total Soluble Solids Content of Newburgh Raspberries from Plots Receiving Varying Amounts of Nitrogen, Phosphorus, Potassium, and Lime F-l Series . Fertilizer BLOCKS Treatments A B C Av. 1 (NiP2Ki ) 6 . 8 6 . 8 8 . 7 . 2 2x ( N ^ ) 6 . 3 8 7.7 7 . 3 3 3 0 * 2 % ) 6.7 7 .4 7 .5 7 . 2 4 ( N ^ ^ ) 6 . 8 7.6 7 . 2 7 . 2 5 ( H ^ ) 6 . 2 8 . 5 8 . 1 7.6 6x (N2P2K3 ) 6 . 2 6 . 4 9 . 1 7 . 2 3 7 (N2P2K.) 6 . 7 7 . 2 8 . 6 7 .5 8 {n3T2K3 ) 6 . 8 8 . 4 7 . 5 7.56 9 (Milorganite) , 6 . 2 6 . 2 9 x (Milorganite) - 7 .9 7 . 3 7.6 1 0 (Check) - 8 . 5 8 . 0 8 . 2 5 1 0 x ( Check) 6 . 8 - *• 6 . 8 C-l Series Fertilizer Treatments B C D Av. 1 (NiP^i ) 9 . 1 - 8 . 8 8 . 9 5 2x ( N 2 P 2 K 1 ) 9 . 1 8 . 5 8 . 8 3 ( N 2 F 2 K _ ) 8 . 2 7 . 5 7 . 8 5 4 ( H ^ j f t ) 9 . 0 «M 9 . 0 9 . 0 5 ( N j P ^ ) 8 . 6 J 9 . 5 9 . 5 9 . 2 6 x ( H ^ 3 ) 9 . 0 1 0 . 5 7 . 5 9 . 0 7 ( H ^ 3 ) 9 . 0 1 0 . 0 9 . 2 9 . 4 8 ( N ^ ) 9 . 4 7 .6 7 .7 8 . 2 9 (Milorganite) «* 7.7 7 .7 . 9x (Milorganite) 8 . 1 7 . 4 - 7.75 1 0 (Check) 9 . 2 9 . 1 9 . 1 5 1 0 x ( Check) 9 . 9 9 . 9 24 1 2x 3 h 5 6x 7 8 9 9x 10 lOx T r e a t m e n t s f i g . j£y Effect of f e r t i l i z e r treatments on edible qua l i ty as determined by tas t ing panel, t o t a l soluble so l ids (refractometer), and t o t a l a c i d i t y i n cc . .1 N NaOH per 100 gms. of j u i c e . 25 5oo Uoo 350 300 10 6x 9x ii.Q 2 K % F - l Series lOx. 9 5 8 6x 33 F-2 Series »(7) Total a c i d i t y in. F - l series Raspberries harvested on J u l y 2U, and F-2 series harvested one week l a t e r . 1 (N-L P 2 K _) 5 ( B ^ P 2 K 3 ) 9 Milorganite 2x ( H 2 P 2 K X ) 3 (N2 P 2 % ) 4 ( N 3 P 2 1 ^ ) 6 x ( N 2 P 2 K 3 , 7 ( N 2 P 2 K 3 ) 8 ( N 3 P 2 K 3 ) 9 x Milorganite 10 Check lOx Check treatments without lime 26 T-Apra x i . Total Acids Content of Newburgh Raspberries from Plots Receiving Varying Amounts of Nitrogen, Phosphorus, Potassium and Lime F-l Series ' Fertilizer BLOCKS Treatments . A B C Av in Ml. of .1 N NaOH per'Ml. of Juice 1 ) 516 466 484 552 505 2x ( N 2 P A ) 604 518 462 514 524 3 ( N ^ ) 540 494 444 522 500 4 ( y A ) 550 510 444 466 492 5 ) 516 516 478 518 507 6 * (N2P2K3 ) 462 464 462 504 473 7 (N 2P 2K 3) 516 462 356 458 448 8 ( N ^ ) 532 500 458 552 460 9 (Milorganite) 528 - 562 545 9 x (Milorganite) •—• 484 468 mm 476 10 (Check) mm 438 472 ** 455 10x(Check) 544 m - 504 524 F-2 Series Fertilizer Treatments B c B Av.y^ in Ml. of .1 N NaOH per'Ml. of Juice 1 ( N ^ i ) 332 - 4P7 3 6 9 . 5 2 x (NjjP^l ) 329 - 314 321.5 3 ( H ^ - ) 421 *- 407 414 4 (N^PjK^ ) 425 - 308 3 6 6 . 5 5 ( N j P ^ ) 407 436 336 393 6 x (N 2P 2 K 3 ) 336 356 393 361 7 (NsPgKj ) 343 288 300 310 8 ( H j P ^ ) 407 377 420 401 9 (Milorganite) 438 43S 9x (Milorganite) 400 393 - 386 10 (Check) 329 347 338 lOx (Check) mm -> 325 325 27 Table 30.1. Total points for edible quality allotted by a tasting panel to Newburgh Raspberries from various fertilizer treatments Treatment color shape texture flavor total 1 ( N x P a K i ) 92 4 2 . 5 4 5 . 5 138 318 2x (N2P2K x) 94 4 8 . 5 4 7 . 5 123 313 79 45 4 1 . 5 117 282.5 u ® 3 ? 2 \ ) 93 4 6 . 5 4 2 . 5 127.5 3 0 9 . 5 5 G ^ E - ) 92 4 0 . 3 4 3 . 6 132 308 6x (N-P^ ) 96 41 .3 4 3 . 3 138, 318.6 7 (N 2P 2K 3) 105 42 4 7 . 3 151.8 347 8 ( N 3 P 2 E 3 ) 82 4 8 . 3 4 2 . 6 129 302 9 (Milorganite) 86 41 42 120 289 9x (Milorganite) 87 4 2 . 5 48 132 3 0 9 . 5 10 (Check) 101 39 4 5 . 5 159 344.5 lOx (Check) 108 43 5 0 . 153 354 TABLE 2111 . Percent Mineral Content (Fresh Weight Basis) of Newburgh Raspberries from Plots Receiving Varying Amounts of Nitrogen. Phosphorus, Potassium and Lime  Fertilizer Treatments F-l Series A B c D C-l Series A B C D Average 1 (N-jBp% ) •406 .333 .364 .303 .375 .330 .352 .315 .347 2x{m2B2K1 ) .385 .330 .358 .326 .382 .449 .348 .327 .363 3 ( N ^ l ) .388 .296 .372 .361 .309 .345 .317 .403 .349 4 (N3P2K3. ) •421 .309 .375 .344 .337 .337 .355 .306 .348 5 (N^K, ) .383 .338 .397 .339 .314 .350 .382 .347 .356 6z:(N2P2K3) .344 .331 .384 .351 .323 .384 .375 .380 .359 7 ( N ^ ) .357 .356 .351 .328 .341 .343 .357 .312 .343 8 (NgPgKj ) .351 .321 .342 .354 .293 .291 .389 .331 .334 9 (Milorganite) .398 . 3 a .392 .341 .308 .300 .346 .338 .346 9z(Milorganite) .447 .313 .447 .313 .380 .368 .383 .370 .378 10 (Check) .358 .319 .358 .319 .365 .336 .364 .335 .344 10x(Check) .437 .320 .437 .320 .342 .339 .342 .339 . 3 a 29 TABLE XLV. Analyses of Variance of Mineral Content of Newburgh Raspberries from Plots Receiving Varying Amounts of Nitrogen, Phosphorus, Potassium and Lime, (using both C-l and F-l series Degrees of Calculated Tabled Source of Variation. SS . freedom . Variance . F. F. Total 117,709 95 Total Treatments 11*576 11 Limed vs. Unlimed (7,550) (l) Block Error 22,556 3 83,577 81 1,052 1.02 7,550 7,519 1,032 7.31 3.96(P= 4 .05) 6.96(Ps: .01) 30 .380 .360 .350 .c! to < % .3U0 CD O U CD * .330 9x Unlimed \ 2x Treatments - 1^____^  — • i ° 7 Limed Treatments > v 8 Fig. (8) Percent ash content in Newburgh raspberries showing contrast between limed and unlimed treatments (Based on average of F l and CI series.) 2 1 ( Y 2 V 3 i y _ _ k (VaV 5 ( N P K ) 1 2 3 6x ( N P K ) 2 2 3 . 7 ( I P X ) ' 2 2 3 8 ( N P K ) 3 2 3 9 Milorganite 9x Milorganite 10 Check lOx Check x- treatments without lime. TABLE XV. Conductivity Readings on the Juice of Newburgh Raspberries as Determined by Soln-Bridge F-l Series Fertilizer Treatments A B C D Average 1 ) a. ( V f t ) .061 .060 Percent .060 .063 NaOH .066 .065 .057 .056 .0610 .0610 .055 .060 .065 .062 .0605 .057 .061 .063 .051 .0580 5 < Y 2 y .060 .062 .067 .057 .0615 6 ± ( H 2 F 2 K 3 ) .054 .060 .060 .060 .0585 7 ( N / 2 K 3 ) .058 .062 .058 .064 .O6O5 8 (NPK ) 3,2 3 . 9 (Milorganite) .056 .055 .060 .060 .058 .058 .0585 .0565 9x(Milorganite) - .058 .063 mm . 0 6 0 5 10 (Check) .058 .061 mm .0595 10x(Check) .056 - mm .053 .0545 C-l-Serie s Fertilizer Treatments A BLOCKS B C D Average 1 (NPK ) 1 2 1 2x (NPK ) 2 2 1 .060 .067 .057 . 0 6 4 .067 .067 .058 .060 .0605 .0645 3 (NPK j 2 2 1 .062 .064 .067 .070 .0660 * < Y A ' 5 ( H ^ K j ) . 0 6 5 . 0 6 5 .066 .055 .0630 .065 .060 .069 .063 .0640 6 * (N 2F 2K 3 ) .061 .058 .062 . 0 7 2 .0630 7 (NPK ) ' 2 2 3 .070 .068 .059 .061 .0645 8 (NPK ) 3 2 3 . 9 (Milorganite) .062 .059 .067 .064 .0630 .062 .061 .066 .O65 .0635 9x(Milorganite) .066 .061 .070 .065 .0655 10 (Check) .062 .062 .064 .064 .0630 lOx (Check) .061 .059 .061 .059 .0600 32 TABLE XVI. Protein Content of Juice from Newburgh Raspberries from Plots Receiving Varying Amounts of Nitrogen, Phosphorus, Potassium and Lime F-l Series  Fertilizer BLOCKS Treatments A B C D Average 1 ( N ^ ) .274 .255 .239 .239 .252 2* ( N ^ ) .284 .240 .246 .245 .254 3 ( N ^ ) .289 .250 .246 .253 .241 4 (N 3P 2 K l) .212 .226 .284 .236 .240 5 ( N ^ ) .289 .279 .250 .255 .271 6z (N2P2K. ) .308 .255 .219 .232 -.253 7 (N 2P 2K 3) .322 .221 .191 .255 .247 8 (N^ P-jK^  ) .274 .265 .279 .234 .263 9 (Milorganite) .332 .312 .312 .294 .312 9x(Milorganite) .275 .260 .284 .256 .269 10. (Check) .250 .250 .255 .244 .250 10_ (Check) .318 .300 .219 .212 .262 TABLE X711. Analyses of Variance of Protein Content of Juice from Newburgh Raspberries from Plots Receiving Varying Amounts of Nitrogen, Phosphorus, Potassium and Lime. -Degree Tabled Source of Variation. S.S. of Freedom. Variance. Calculated F. F. Total 47792 47 1,017 Total Treatments 14979 11 1,362 2,05 Low Nitrogen vs. High Nitrogen ( 1399 (1) 1,399 2.10 Block I O 8 6 4 3 3,621 5.44 Error 21949 33 665 33 TABLK XVlll. Protein Content of Newburgh Raspberries from Plots Receiving Varying Amounts of Nitrogen, Phosphorus, Potassium and Lime C-l Series Fertilizer BLOCKS Treatments A B C 3 Average 1 ( H i p A } 1.120 1.087 1.178 1.157 1.135 2x % > 1.028 1.203 1.144 1.232 1.152 3 1.058 1.146 1.158 1.218 1.145 4 ( V A > 1.046 1.150 1.184 1.192 1.148 5 ( ^ 2 * 3 ) 1.040 1.013 1.124 1.184 1.090 6_ (N2P2K3 ) 1.100 1.113 1.132 1.180 1.131 7 (N2P2K3 ) I.I70 1.120 1.073 1.218 1.145 8 (N3P2K3 ) 1.098 1.100 I.248 1.208 1.163 9 (Milorganite) 1.168 1.121 1.147 1.100 1.134 9x (Milorganite) 1.155 1.191 1.146 1.143 1.149 10 (Check) 1.160 1.198 1.088 1.126 1.143 10_ (Check) 1.126 1.117 1.098 1.093 1.108 34 DISCUSSION When nitrogen is applied abundantly i t tends to produce rank vegetative growth, often at the expense of quality of fruit (19)» Das (7) found that increasing the application of nitrogen to sugar cane increased the leaf area but decreased the concentration of sucrose in the expressed sap. Other workers report similar results (31,7»8)« The results in this particular experiment are in accord with the above, that i s , the high nitrogen treatments lowered the percentage sugar content in the raspberries and at the same time tended to produce more ab-undant foliage. The explanation for this lowering of sugar content lies perhaps in the fact that, in the presence of an abundant supply of nitro-gen, the carbohydrates are being utilized more rapidly in the formation of organic nitrogenous compounds, thereby decreasing the amount of reserve carbohydrates. It will be remembered that there was a tendency for the protein content of the berries to be higher in the high nitrogen treatments-even though the difference did not prove to be significant. Regarding the results of varying nitrogen levels on the vitamin C content of the fruit there was a tendency for i t to increase with in-creasing nitrogen applications from the low nitrogen level up to the med-ium level and then to decrease at the high levels. It would appear then, that there is an optimum level of nitrogen beyond which the vitamin C con-tent tends to be lowered. The more outstanding effect on the vitamin C content was that which resulted from the applications of lime. Either liming interfered directly or indirectly with the synthesis of vitamin C, or, by neutralizing 35 the organic acids in the plant (19), i t created a situation whereby vit-amin C was rendered less stable. As high nitrogen fertilizer treatments have frequently been reported to interfere with vitamin C production (for example 1,9,) there is the possibility that liming caused the nitrogen to become more available and thus affected the vitamin C content indirectly. Miller (19) cite« several examples which indicate that nitrogen, supplied as ammonium sulphate, is more available when the soil reaction is close to neutral;, or above, than at a lower pH. Since ammonium sulphate fertilizer was used in this experiment and since the soil reaction is well below neu-tr a l , the application of lime could very easily have increased the absorp-tion of nitrogen. Another interesting feature with respect to the vitamin C con-tent is the apparent regulating effect of potassium on calcium. If we ac-cept the theory that lime lowered the vitamin C content by making more ni-trogen available to the plant, it would be reasonable to assume that a high level of potassium minimized this effect by interfering with the cal-cium intake and consequently, also with the availability of nitrogen. In other words, the addition of potassium might have had a regulatory effect on the nitrogen intake, thereby affecting the vitamin 0 content. The real cause for the depressing effect of lime on the mineral content is difficult to determine since only total Minerals and not the in-dividual elements were determined. However, in view of the fact that rasp-berry fruit is high in potash and phosphoric acid (34), i t would seem that liming interfered with the absorption of either phosphorus or potassium,or both. Since the lime and fertilizer applications were made only one week apart conditions might easily have been created which facilitated phosphor-us fixation, especially as both lime and fertilizer were applied broadcast. 36 That potassium absorption should be retarded through liming could be accounted for by the retarding effect of one ion on another. Cal-cium is a slow moving ion and retards the rate of entry of other ions. Generally speaking, the high nitrogen treatments increased total acidity (fig . 6 ) . Since acidity is to a Large extent a by-product in the metabolism of nitrogenous compounds, this relationship would be expected. The drastie decrease in total acids between fruit harvested on July 24, and that harvested on July 31, is perhaps partly due to the some-what riper condition of the later harvested fruit. According to a report in Technical Bulletin 403, U.S.D.A., (28), both water content and total ac-idity of raspberry fruit decline during the ripening stage. However, the greater part of the drop in total acids must be attributed to variations in climatic conditions, which have been shown to exert a considerable in-fluence on total acidity. Schupan (25), for instance, found that in straw-berries the acidity increased,markedly after a rain. Recognizing the fact that total acidity is so readily influenced by climatic conditions, one can see the difficulty of using individual de-terminations as a criterian of quality. The various fertilizer treatments had no: consistent effect on total solids, (dry weight). The marked increase in total solids in the fruit from the two plots which suffered from excessive moisture deserves -mention even though the treatments had no direct bearing on the results. The plants in these plots were definitely stunted for lack of nutrients. Under such conditions the plant forms small, thick-walled cells which ac-count for the higher percentage of total solids, (dry weight). In respect to taste panels i t is recognized that they have a def-inite place, in the determination of edible quality. The validity of taste 37 panel results, however, depends largely on how much care is exercised in eliminating a l l human error possible. The general consensus of opinion is that personnel can be trained for greater accuracy in detecting the var-ious sensations that determine flavor. Other workers (5)» however, re-port no difference in results obtained with trained and untrained personn-e l . In this particular experiment the organoleptic results are cor-related with total soluble solids and total acids. Of the four most common taste sensations, sweetness, sourness, bitterness and saltiness, i t is apparent that the first two were the de-ciding factors in determining the flavor of the berries. The taste panel showed a preference for the berries with the highest sugar and lowest acid content and, conversely, the least popular berries were those with the low-est sugar and highest acid content. The sweeter berries resulted from the low nitrogen, high potassium treatments, whereas, the more acid berries came from the high nitrogen treatments. No consistent differences were de-tected in the general appearance of the frozen product as a result of fer-t i l i z e r treatments. 38 A B S T R A C T " SUMMARY AND CONCLUSIONS Twelve fertilizer treatments consisting of varying levels of nitrogen, phosphorus, potassium and calcium, were applied to plots of New-burgh raspberries laid out in four randomized blocks. The fruit was an-alyzed for total sugars, vitamin C, total solids, soluble solids, proteins, total acids, total minerals, flavor and freezing quality in order to ascer-tain the effect of the various fertilizer treatments on the quality of the fruit. It was found that: 1. High nitrogen treatments decreased the sugar content, tended to decrease the vitamin C content, and increased the acidity of the berries, 2. Liming decreased both vitamin C and mineral content. 3. An abundant supply of potassium appeared to be beneficial in that it minimized the effects of lime and tended to have a regulatory effect on nitrogen absorption. 4. Quality, as distinguished organoleptically, was correlated with high sugar and low acid content of the berries, and conversely, lack of quality was correlated with low sugar and high acid content. The former re-sulted from low nitrogen, high potassium treatments, while the latter was produced by high nitrogen fertilizer treatments. 39 LITERATURE CITED 1. Anstey, TJ3. The effect of varying fertilizer constituents on the food value of the carrot. A Thesis submitted for the degree of Master of Science in Agriculture, University of British Columbia, 1943* 2. Association of Official Agricultural Chemists, Methods of Analyses. A.O.A.C., Washington, D.C., 1945» 3. Atkinson, F.E., and Strachan, C.C. Chemical constituents of some fruits grown in B.C. Sci. Agric. 20:321-28, Feb. 1940. 4* Bartholomew, E.T., and Sinclair, W.B. Soluble constituents and buffer  properties of orange juice. Plant Phys. 18:185*206, 1943• 5« Currence, TJfl., and Larson, Russell. Refractive index as an estimate  of quality between and within muskmelon fruits. Plant Phys. 16:611-620, 1941. 6. Darrow, GJ_., U.S.D.A. Effect of fertilizer on firmness and flavor of strawberries in N.C. Proc. Amer. Soc. Hort. Sci., 28:231-35* 7. Das, U.K. Nitrogen nutrition of sugar cane. Plant Phys., 11:251-317, 1936^ 8. Gourly, G.H. Relation of nitrogen to storage quality of fruit. Sci. Agric, 11:130-36. 9. Hammer, K.C., and Maynard, L.A. Factors influencing the nutritive value of the tomato. U.S.D.A. Misc. Pub., 5Q2:9, 1942. 10. Harding, Paul L., and Wadley, F.M. Study of quality in temple or-anges. Food Res. 10: 510-17, 1945. 11. Harris, G.H. The cuthbert raspberry in B.C. Sci. Agric. 20, Feb., 1940. 12. Harris, G.H., and Woods, J.J. Raspberry nutrition 1. Sci. Agric. 15, April, 1935. 13. Haynes, D. and Archbold, H.K. Chemical studies in the physiology of apples. Ann. Botany 42: 168, pp 965-IOI7, Oct., 1928. 14. Hornby, C.A. Responses of the cuthbert raspberry to mineral treat-ments . A Thesis submitted for the degree of Master of Science in Agriculture, University of British Columbia, 1940, 15. Jones, W.W., and Parker, E.R. Ascorbic acid-nitrogen relations in naval orange juice as affected by fertilizer applications. Proc. Amer. Hort. Sci., 50:195-98, 40 16. Kayser, R. Ztscli off. Chem., 12:155, 1906. 17. KrayMll, H.R, Plant metabolism studies as an aid in determining fertilizer requirements. 1, Ind. and Eng. Chem., 22:275-76,' 1930. 18. MacG-illivray, J.H. The importance of phosphorus in the production of seed and non-seed portion of a tomato fruit. Proc. Amer. Soc. Hort. Sci., 22:374-79, 1926. 19. Miller, E.C., Plant Physiology. McGraw-Hill Book Company, Inc., New York, 1938. 20. Morgan, M.F. Universal soil testing system. Conn. Expt. Sta. Bui. 372, 1935. 21. Newton, J.D. The selective absorption of inorganic elements by various crop plants. Soil Sci. 26:85-91. 22. Paterson, D.D. Statistical technique in agricultural research', McGraw-Hill Book Co., Inc., New York and London, 1939. 23. Reed, H.S. The value of certain nutritive elements to the plant c e l l . Ann. Bot., 21: 501-543, 1907. 24. Robinson, W.B., and Stotz. Jr. Biol. Chem. 160:217, 1945. 25. Schuphan, W. Die Veralnderung der Vit. C. u. kalorischen Wertstoff-gehalte bei-deutschen Erdbeersorten unter dem Einfluss  schonen u. schlechten Wetters. Hort. Abstracts, Imp. Bur. of Hort., Vol. 12, 774. 26. Sinclair, W.B.,and Bartholomew, E.T., Compositional factors affect-ing the edible quality of oranges. Proc. Amer. Soc. Hort. Sci., 50:177-86. 27. Soil Survey of the Lower Eraser Valley. Pub. 65O, Tech. Bui. 20, Dom. Dept. of Agric. 28. U.S.D.A. Tech. Bui. 148. The frozen pack method of preserving berr-ies in the pacific northwest. 29. U.S.D.A. Tech. Bui. 403. Hydrion concentration changes in relation to growth and ripening in fruits. 30. Utah Station Bui. 306, 1943. Freezing preservation of Utah fruit. 31. Vereier, J. Jour. Soc. Nat. Hort. France 15, 349. 32. Verner, L., Effect of nitrate fertilization on apple fruits. Proc. Amer. Soc. Hort. Sci. 30: 32-36, 1933 41 33* Winter, J.D. University of Minnesota, St. Paul, Minnesota. Straw- berry and Raspberry varieties for freezing storage. 34. Winton, A.L. The structure and composition of foods, New York, John Wiley and Sons, Inc., 1935. 

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