TY - GEN AU - Nadia Ahmed Mohammed Hamed AU - Abdelrahman Mohamed Abdelrahman , AU - Ahmed Hussien Hanafy Ahmed , AU - Mohamed Khalil Khalil Aldodo , TI - Some physiological studies on the nutrition of citrus / PY - 2005/// CY - Cairo : PB - Nadia Ahmed Mohammed Hamed , KW - Nutrition of citrus KW - Some physiological studies N1 - Thesis (M.Sc.) - Cairo University - Faculty Of Agriculture - Department Of Plant Pathology and Physiology; Issued also as CD N2 - The present study was carried out during two successive seasons of 2001 and 2002 to study the effect of different levels of Zn (0 , 375 and 75 ppm) , tryptophan (25 , 50 and 100 ppm) , IAA (100 , 200 and 300 ppm) , copper oxychloride (0 , 25 , 5 and 75 g / l) , foliafeed D (0625 g / l) or compound fertilizer (5 g / l) foliar applications on growth , fruit yield and fruit quality of Valencia orange treesAlso , the replacement of Zn foliar application with tryptophan or IAA was investigatedGenerally , the results reveal that all treatments improved most of the studied growth characters , yield and fruit quality through their favourable effects on leaves chemical composition ; plant pigments , total sugars , total soluble phenols , total free amino acids , tryptophan and endogenous plant hormones balance of leaves as well as nutritional status (N , P , K , Mg , Zn , Cu , Fe and Mn concentrations) of leaves , shoot and pruning wood) Moreover , the results indicate that , tryptophan foliar application at the rates of 25 , 50 and 100 ppm and IAA at the rates of 100 , 200 and 300 ppm , to some extent , can be replace zinc foliar application at the recommended dose (375 ppm Zn) ER -