Nutritional Fruit Research Articles

INTERSTOCK EFFECTS UPON APPLE LEAF AND FRUIT MINERAL CONTENT

To study interstock effects upon mineral content of apples, four cultivars, Golden Delicious, Delicious, McIntosh and Spartan, were used as scions and interstocks in 16 combinations on M9 rootstock. N, P, K, Ca, Mg, Fe, Mn and Zn were analyzed in leaves from 1971 to 1975 and Ca, Mg and K in fruits in 1975. There were many scion effects. Accumulation of P and Fe in the leaves and K and Ca in the fruits was greater in Delicious than in the other cultivars. Leaf levels of Ca and Mg were greatest in Golden Delicious. Leaf Zn, K or N content differed slightly among the cultivars. There were but slight interstock effects or scion × interstock interactions. Hence, leaf and fruit nutrition did not depend upon the interstock.

The Effect of Temperature on Growth and Mineral Nutrition of Fruits of Apple, with Special Reference to Calcium

AbstractGrowth and mineral composition of fruits in potted trees were studied at two temperatures (19 and 24°C) in two experiments with Golden Delicious and one with Cox's Orange Pippin under a controlled environment. In Golden Delicious the high temperature promoted fruit growth markedly, but in Cox's Orange Pippin the stimulation was much less pronounced.The levels of K, N, Mg, and P (expressed as amounts per fruit) were increased at the higher temperature. This increase was almost completely the result of differences in fruit growth. With respect to Ca the high temperature reduced Ca influx in one Golden Delicious experiment and had hardly any effect in the other, but favoured influx in Cox's Orange Pippin. In one Golden Delicious experiment the temperature was raised 7 weeks after blossoming, which resulted in a temporary drop of Ca. When the same temperature change was applied 4 weeks earlier, Ca continued to increase.It is assumed that mineral influx occurs via the xylem during the first few weeks after fruit set and via the phloem throughout. The results are discussed in terms of differences in mobility in the phloem for the various minerals and of a shift in the ratio between xylem and phloem movement induced by differences in the growth rate of the fruits.

Phloem bleeding from legume fruits?A technique for study of fruit nutrition

Bleeding from phloem of cut distal tips of attached fruits was demonstrated in the genera Spartium, Genista, Lupinus and Jacksonia. Bleeding occurred over a 2-25 min period enabling 0.5-10 μl of sap to be collected from a fruit. A detailed study of Lupinus albus L. showed that exudation rate declined exponentially after cutting, but without any change with time in solute levels in exudate. Bleeding resumed at its initial rate and solute concentration on recutting the fruit tip.Phloem exudates had a high pH (7.8-8.0), a sucrose content of 100-210 mg ml(-1) but only traces of monosaccharides. Surrounding pod tissues contained only 15-35 mg ml(-1) of sugars (tissue water basis) more than two thirds of this monosaccharide. Amino compounds were present in phloem exudates at 8-28 mg ml(-1), asparagine and glutamine predominating but a wide spectrum of other amino acids being also present. No significant differences in levels of organic solutes were observed in phloem exudates collected from tips of attached versus detached fruits, from phloem exudates collected from fruit tips versus pedicels, or from basal versus distal ends of a detached fruit.Potassium was the major cation (1.5-2.2 mg ml(-1)) of the phloem exudate, Ca(2+) was at a much lower level than either Mg(2+) or Na(+). Trace element levels in phloem exudates appeared to be influenced by availability to the plant from the rooting medium. Nitrate was absent though detectable in non-vascular tissues of the shoot. (14)C- labelled assimilates were detected in exudates of L. albus one hour after feeding a source leaf (14)CO2; sucrose, organic acids and certain amino compounds achieved high specific labelling. (14)CO2 feeding studies coupled with the phloem bleeding technique revealed highly specific source-sink relationships between foliar organs and fruits of the primary inflorescence.

Nutritional Beverages from Acid Whey Powder

Blending acid whey powder (AWP) with frozen, concentrated fruit juices, fresh fruit crystals or flavored powder bases produced acceptable nutrient beverages.Orange, grapefruit, and pineapple juice nutrient beverages showed excellent flavor, texture, and appearance qualities with 4% of powder in the reconstituted product and good qualities at 6% levels. Lemon juice, grape juice, and flavored powder nutrient beverages scored lower because of sedimentation.The acid reaction of a fruit juice and flavored powder base was retained in the nutritional fruit juice. In reconstituted orange nutrient beverage containing 6% whey powder, the maximum pH shift was from 3.75 to pH 3.96.

Soil and leaf analysis in relation to fruit nutrition

AbstractThe pros and cons of soil and leaf analysis are discussed in relation to the N, P, K and Mg nutrition of fruit crops. In general, soil analysis is not entirely satisfactory for predicting the response of fruit crops to N, P and Mg: a better relationship exists between soil‐K, crop response and plant‐K. Leaf analysis based on correct sampling procedure and interpretation, has proved most useful for diagnosing the current nutrient status of fruit crops in relation to deficient and sufficient (optimum) nutrient supply.

Investigations, on The Nutrition of Fruit Trees.: Some Effects of Deficiencies of Nitrogen, Potassium, Calcium and Magnesium, with Special Reference to the Behaviour of Certain Varieties of Apple Trees.

(1930). Investigations, on The Nutrition of Fruit Trees.: Some Effects of Deficiencies of Nitrogen, Potassium, Calcium and Magnesium, with Special Reference to the Behaviour of Certain Varieties of Apple Trees. Journal of Pomology and Horticultural Science: Vol. 8, No. 4, pp. 316-344.