The beneficial effect on yield and quality of `Anna' apple fruits for the application of ascobine at 0.1% and citrine at 0.6% was studied during 1995 and 1996. Results showed that two citrine sprays at start of growth and 30 days later of ascobine at 0.1% or citrine at 0.6% were of material promotion effect on yield, fruit weight, total soluble solids, and total sugars, while reducing the total acidity. Both fertilizers were equally very effective in all the studied characters. The most striking and promising treatment was the application of ascobine at 0.1% or citrine at 0.6% twice during the growing season; i.e., growth start at 30 days later.
F.F. Ahmed, A.M. Akl, A.A. Gobara, and A.E.M. Monsour
Chiwon W. Lee, Keun Ho Cho, Larry J. Cihacek, and Robert W. Stack
The influence of calcium nitrate fertilization on the storage characteristics of carrot (Daucus carota) roots was investigated. Plants of `Navajo' carrots grown under irrigation were sprayed with a 2% solution of Ca(NO3)2 4H2O at a rate of 50 kg/ha Ca 10 days before harvest. Quality of carrot roots stored at 5 °C was evaluated monthly for sweetness, tissue electrolyte leakage, disease development and visual characteristics. For disease development, the crown portion of the carrot roots was inoculated with an ascospore solution (2 × 109 spores/mL) of white mold (Sclerotinia sclerotiorum) before storage. When determined after 1 month of storage, percent tissue electrolyte leakage in the Ca-treated carrots decreased 52% as compared to that obtained from the control. Sugar contents of the cortex and xylem tissues were not affected by calcium nitrate fertilization. Changes in other quality parameters of carrot roots for an extended storage period, including white mold development, will be presented. Initial findings of this research suggest that foliar calcium feeding at the final stage of plant growth may enhance the quality of carrot roots during storage.
A.M. Akl, A.M. Wassel, F.F. Ahmed, and M.A. Abdel Hady
This investigation was conducted during the 1991, 1992, and 1993 seasons to study the effect of different concentrations and number of sprays urea and/or boric acid on yield and berries quality of Red Roomy grapevines. Two, three, four, or five sprays for both urea at 0.5% 1%, or 1.5% and /or boric acid at 0.1%, 0.2%, or 0.3% in addition to the control treatment were applied. Combined sprays of urea and boric acid was preferable in increasing the number of clusters, yield per vine, berry set parentage, fertility coefficient. weight, length and shoulder of cluster, weight and dimensions of berry, total soluble solids, total sugars, and total anthocyanins in grapes and in reducing the percentages of cracked and shot berries and the total acidity compared with the single application of both. Spraying urea at 1.0% in combined with boric acid at 0.2% four times (i.e., at growth start, first bloom, immediately after berry set, and at 30 days later) is recommended for achieving high yield and fairly good berries quality in `Red Roomy' grape vines.
J.A. Franco, P.J. Pérez-Saura, and A. Durán
The appearance of blossom-end rot (BER) in tomato is related to a decrease in the absorption and translocation of Ca due to excessive salinity in the soil solution. An experiment was conducted to investigate the effects of calcium nitrate (NT), EDTA-Ca (ED) and Aminoquelant-Ca (AQ)—a product containing Ca, B and protein hydrolisate—on the yield and incidence of BER when applied to the leaves of tomato (Lycopersicon esculentum Mill. `Durinta') grown in the open with a drip irrigation using saline water from a well (mean ECw 5.2 dS·m–1). The three calcium treatments and control were replicated four times, with 12 plants per replication, in a completely randomized design. Although yield per plant was higher with AQ, the difference was not statistically significant. Fewer fruit were affected by BER after treatment with ED and AQ than with NT and in the control. Leaf Ca concentration did not differ significantly between treatments. However, leaf B concentration was higher after treatment with AQ. Fruit Ca and B concentrations did not differ significantly in any treatment. The total free amino acids content in leaves was higher after AQ treatment than in the other treatments and control, although no significant difference was observed between the treatments in the fruit.
G.R. Stino, A.E. Abou Aziz, A.A. Elezaby, and E.A. Abd Elmoneim
Valencia orange trees [Citrus sinensis (L.) Osb.], budded on sour orange (C. aurantium) rootstock, were sprayed with four different potassium salts during 1995 and 1996. Twenty 5-year-old trees were sprayed once per month with one of the following material. K0: distilled water, K1: potassium green (a compound of different potassium salts, 35% K2O), K2: potassium nitrate (35% K2O), K3: potassium citrate (35% K2O), or K4: potassium sulfate (51% K2O). The vegetative growth occurred in three distinct successive cycles, i.e., spring, summer, and autumn. These cycles differed in time of commencement, duration and termination with respect to season. All potassium treatments significantly increased the shoot length and number of leaves/shoot for the three growth cycles. However, potassium green was superior overall other treatments. Percentage of leaf miner infestation was reduced at all potassium treatments. Potassium applications significantly increased leaf contents of N, P, K and decreased Ca and Mg levels.
A.M. Akl, A.M. Wassel, F.F. Ahmed, and M.A. Abdel Hady
This study was performed during the 1991, 1992, and 1993 seasons to study the effect of different concentrations and number of sprays urea and/or boric acid on behavior of buds, vegetative growth, and vine nutritional status of Red Roomy grape vines. Two, three, four, or five sprays for both urea at 0.5%, 1.0%, or 1.5% and/or boric acid at 0.1%, 0.2%, 0.3% in addition to the control treatments were applied. A gradual increase was observed in the percentages of burst and fruiting buds, main branch length, leaf area, cane thickness, total chlorophyll, and total carbohydrates in the leaves and considerable depression was observed in the percentages of dormant and vegetative buds. The most pronounced effect on growth and nutritional status was detected on vines sprayed four times with urea at 1.0% plus boric acid at 0 2% during the growing season.
Lenny Wells, Jason Brock, and Tim Brenneman
regarding the effect of foliar urea sprays on pecan production. The objectives of this study were to investigate the effects of foliar application of elemental S and urea on pecan leaf tissue N and S concentration, pecan nut quality, LCI, and pecan scab
Xunzhong Zhang, Mike Goatley, Jamie Conner, Megan Wilkins, Inna Teshler, Jun Liu, Michael Fefer, and Wenzi Ckurshumova
-0075 solution was made by mixing 0.1% Cu-Chl with 0.5% synthetic paraffinic oil and 0.04% emulsifier in distilled water. The treatments included 1) well-watered control, 2) drought control, 3) B18-0074 applied as soil drench plus foliar application, 4) B18
Augusto Ramírez-Godoy, María del Pilar Vera-Hoyos, Natalia Jiménez-Beltrán, and Hermann Restrepo-Díaz
., 2016 ). In this context, foliar Si applications increased the mortality of tobacco whitefly nymphs on cucumber ( Cucumis sativus ) ( Correa et al., 2005 ). Soil fertilization with calcium (Ca) or potassium silicate favored resistance to arthropods in
M. Lenny Wells, Patrick J. Conner, J. Frank Funderburk, and Jacob G. Price
Foliar boron (B) applications have been observed to promote flowering, fruit set, and yield in a variety of perennial tree crops ( Batjer and Thompson, 1949 ; Hanson et al., 1985 ; Nyomora et al., 1999 ; Stephenson and Gallagher, 1987