No abstract

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.

To economically evaluate production in terms of quality and quantity in newly reclaimed area of desert under drip irrigation system an investigation was conducted for two consecutive seasons in a vineyard to scrutinize the effects of natural zeolite loaded nitrogen, biochar, biofertilizers, nano rice husk with and without nitrogen and organic fertilizer as well as combination of them in comparison to vines fertilized with chemical recommended dose of NPK as control on growth, and chemical components of Superior seedless grapevine cultivar (Vitis vinifera L). The outcome data revealed that, mixed between natural zeolite loaded nitrogen, biochar, biofertilizers (Bacillus megaterium and Azotobacter chroococcum), rice husk loaded nitrogen and compost in one mixed treatment led to significant increase in vegetative growth as well as chemical ingredients. Moreover, mixed treatment markedly improved soil chemical and physical properties. Present results confirmed that, mixture of zeolite loaded nitrogen, biochar, biofertilizers, nano rice husk loaded nitrogen and organic fertilizers could supply grape with all essential and beneficial nutrients to achieve high yield with desired market criteria alongside reducing economic costs which reflected from evaluation of investment factor and decline pollution of our ecosystem.

No abstract

This investigation was carried out on 13-year-old Valencia orange trees [Citrus sinensis (L.) Osbeck] budded on five different rootstocks. Heat unit accumulation (temperature above 12.5 °C) for fruits worked on the various rootstocks were calculated from full bloom to maturity stage. Valencia fruits on Troyer citrange (C. sinensis × Poncirus trifoliata) and Carrizo citrange (C. sinensis × Poncirus trifoliata) rootstocks matured earlier when compared to those growing on Cleopatra mandarin (C. reticulata Blanco), Volkamer lemon (C. volkameriana Ten. and Pasq.), and sour orange (C. aurantium) rootstocks. The results showed that the Valencia fruits, regardless of rootstock, could be stored for different periods under different conditions. However, in order to avoid degradation in fruit quality, storing periods should not exceed 21, 60, and 120 days under room conditions (25 °C and RH 25% to 35%), 4 °C (RH 80% to 85%), and 8 °C (RH 80% to 85%); respectively.