EFFECT OF FOLIAR APPLICATION OF ANTIOXIDANTS ON VEGETATIVE GROWTH AND LEAF MINERAL CONTENT OF CHINESE TANGERINE YOUNG TREES BUDDED ON SOME CITRUS ROOTSTOCKS GROWN UNDER SALINE CONDITIONS

摘要

Wady El Natroun high way (Beer Hooker Area) in a private orchard in a sandy soil under drip irrigation system with saline water. in 2015 and 2016 seasons. Chinese tangerine (Citrus tangerine) transplant were budded on three rootstocks namely sour orange (Citrus aurantum, mion), volkamer lemon (Citrus volkameriana, Tem) and X639 hybrid between (Cleopatra mandarin × Ponicurus trifoliata) grown under saline conditions to study the effect of foliar application of antioxidants namely ascorbic and salicylic acid on vegetative growth and leaf mineral contents. Results showed that, Volkamer lemon rootstock surpassed sour orange and x639 rootstocks under saline conditions, the highest incremental percentage young tree height, stem diameter, number of leaves per shoot and leaf area were registered by Chinese tangarine scion budded on Volkamer lemon rootstock. Among selected antioxidants ascorbic acid at the concentrations of 800 ppm recorded the highest significant values for vegetative growth parameters and surpassed salicylic acid. Also Chinese mandarin scion budded on volkamer lemon accumulated the highest concentrations of nitrogen (N), phosphorus(P), magnesium(Mg), and chloride (Cl-) and the lowest concentration of sodium (Na+). Chinese mandarin scion budded on sour orange rootstock accumulated the highest concentrations of potassium (K) while Chinese tangerine scion budded on x639 accumulated the highest concentrations of sodium (Na).