concerning how such an interaction would affect fruit mineral concentration and fruit quality at harvest. This study was designed to test whether reducing crop load in response to deficit irrigation has negative consequences for leaf and fruit nutrition of
Gerry H. Neilsen, Denise Neilsen, Sung-hee Guak and Tom Forge
Within the Cucurbitaceae are two genera, Cucumis and Citrullus (muskmelons and watermelon, respectively), with sweet-tasting fruits. Per-capita consumption of these two genera rank melons (11.6 kg) second only to bananas (12.6 kg) as the most-consumed fruit in the United States. Consumption of melons, especially muskmelon and honey dew fruits, is significant from the standpoint of their nutritional benefits to humans. Orange-fleshed melons provide a person with 100% of their daily requirement of vitamins A and C. Melons also are a significant source of nutrients: sugars, dietary fiber, calcium, iron, potassium, and “phytochemicals.” Phytochemicals are compounds not presently recognized as having nutrient value. Thirty-eight known phytochemicals are in melons and have preventive properties in addition to anti-cancer attributes. Use of beta-carotene-rich melons is important in chemopreventive trials. Melon production and genetic factors may affect human health-beneficial nutrient and phytochemical quality attributes.
This article examines the nutritional quality and human health benefits of melons, specifically, muskmelon or cantaloupe (Cucumis melo L. var. reticulatus Naud.) and honeydew melon (Cucumis melo L. var. inodorus Naud.) types. Melons are naturally low in fat and sodium, have no cholesterol, and provide many essential nutrients such as potassium, in addition to being a rich source of beta-carotene and vitamin C. Although melons are an excellent source of some nutrients, they are low in others, like vitamin E, folic acid, iron, and calcium. Since the U.S. diet is already high in fat and protein content, melons should be included in everyone's diet, along with five to eight servings per day of a variety of other fruit and vegetables, to ensure adequate nutrition, promote individual health, and reduce one's risk of cancer and certain other chronic diseases.
Xinhua Yin, Clark F. Seavert, Janet Turner, Roberto Núñez-Elisea and Helen Cahn
row area on soil nutrient availability, leaf and fruit nutrition of young sweet cherry, and cash costs and returns; and (2) evaluate the impacts of synthetic polypropylene groundcover in the row area on soil moisture and temperature and the growth
Esmaeil Fallahi and S. Krishna Mohan
The influence of four rootstocks and four levels of nitrogen supply on tree growth, precocity, fruit quality (size and color), leaf mineral concentrations, and fire blight [Erwinia amylovora (Burrill) Winstow et al.] severity in `Scarlet Gala' apple (Malus domestica Borkh.) trees was studied between 3 to 4 years. Trees that received an annual ground application of 0.15 lb (68 g) actual N as urea over four growing seasons had greater trunk cross-sectional area (TCA), higher yield, better fruit color, lower leaf N and less fire blight than those which received higher amounts of N. Trees on Malling (M.9) were more precocious and had higher yields in early years while trees on Malling-Merton 106 (MM.106 EMLA) and Malling-Merton 111 (MM.111 EMLA) had higher production 4 years after planting. Trees on Malling 26 (M.26 EMLA) had higher leaf Mg than those on other rootstocks. Trees on M.9 and M.26 EMLA had more fire blight damage than those on other rootstocks.
Jujube or chinese date (Ziziphus jujuba) has fruit that is developed mainly from ovary plus some nectary disk tissue, and the fruit can appear smooth or bumpy on the surface. The objective of this study was to investigate the unique fruit development of ornamental ‘Teapot’ jujube. Unlike ‘Li’ and ‘Lang’, ‘Teapot’ jujube fruit had one to five protuberances on the shoulder of the fruit and few entirely lack protuberances. The stamens of ‘Teapot’ jujube flowers were fewer in number, misplaced in location, and deformed in shape—some stamens were anthers only while others were filament only. Deformed stamens of ‘Teapot’ jujube were always anchored in the nectary disk instead of at their normal location—near the edge of the nectary disk. After bloom, the residue of stamens, nectary disk, and ovary were all constituents of the developing fruit. The deformed stamens developed into the fleshy protuberances and equaled them in number. Fruit with only two protuberances predominated, which is how the ‘Teapot’ jujube acquired its name, but the ratio among protuberance categories varied between trees. With its unique and decorative fruit shape, and acceptable fruit quality, ‘Teapot’ jujube could be used as a backyard tree, both as an ornamental and for its fruit.
Alexander Lang and Richard K. Volz
The effects of spur leaf removal on xylem sap flows and calcium accumulation in fruit of apple (Malus ×domestica Borkh. `Royal Gala') were determined 56 to 61 days after full bloom. Fruit calcium concentrations were reduced but fruit size was not influenced by partial spur defoliation at bloom. Apples exchanged xylem sap with the tree in daily cycles of flow reversal. The presence of local spur leaves promoted this exchange by accentuating the xylem sap drawn out of the fruit during the day, requiring more to flow back into the fruit at night to replace it. Calcium concentrations were lower in the xylem sap leaving the fruit than in that entering it. The reduced calcium accumulation in the fruit borne on defoliated spurs can therefore be attributed to the reduced volume of xylem sap exchanged between tree and fruit.
A. Delgado, M. Benlloch and R. Fernández-Escobar
Change in B content of olive (Olea europaea L.) leaves during anthesis reveals the appearance of a potent B sink. This phenomenon was more marked in young leaves of bearing trees with a high degree of flowering than in nonbearing trees with a low degree of flowering. Applying B to the leaves at the time of anthesis increased the B concentrations in leaf blades, petioles, bark of the bearing shoot, and flowers and fruit 3 days after treatment. The results suggest that B is mobilized from young leaves during anthesis to supply the requirements of flowers and young fruit.
R. Fernández-Escobar, D. Barranco and M. Benlloch
Chlorotic `Manzanillo' olive (Olea europaea L.) trees and `Maycrest' peach [Prunus persica (L.) Batsch] trees were injected with Fe solutions using an apparatus that consisted of a plastic injector and a pressurized latex tube containing the solution to be injected. Injections were made on various dates from Sept. 1987 to July 1988. All treatments increased chlorophyll content compared to that of the control. Ferrous sulfate was the most effective Fe compound in alleviating chlorosis; its effect lasted for two seasons in peach and for at least three seasons in olive. Also, ferrous sulfate increased vegetative growth and affected cropping the year following injections. Ferrous sulfate at 0.5% to 1% is recommended to reduce the risk of foliar burning. The injection method effectively introduced Fe compounds into olive and peach trees.
This article summarizes jujube importation and culture history and current jujube cultivars in the United States. Described within are jujube taxonomy, biology, adaptation, fruit nutrition, pests and diseases, propagation, and research conducted in the United States. It also discusses the current issues with jujubes in the United States and possible solutions to them. Jujube adapted and grew well in the southern and southwestern United States, and it could become a valuable industry in the United States within 15 to 20 years.