PRODUCTIVITY OF GIZA 177 RICE VARIETY GROWN AFTER DIFFERENT WINTER CROPS AND FERTILIZED WITH DIFFERENT NITROGEN LEVELS

Two field experiments were conducted at the Rice Research and Training Center (Etai El-Baroud Agricultural Research Station Farm) to study the effect of different preceding crops and different nitrogen fer­tilizer levels on the productivity of Gin 177 rice cultivar in two consecu­tive seasons (1996 and 1997). Rice was grown after clover, broad bean. red radish and wheat. Nitrogen fertilizer was applied to the rice crop at the rate of 0. 96 and 144 kg N/ha in the urea form. The main results in­dicted that increasing nitrogen levels up to 144 kg/ha significantly in­creased plant height, panice length, plant biomass, grain yield and yield and yield components as well as harvest index in the two growing sea­sons regardless of the previous crop. Highest values of yield and yield components were obtained when rice was grown after legume crops fol­lowed by red radish, while the lowest values of these traits were ob­tained when rice was grown after wheat in both seasons. Data showed also that nitrogen controgen content and uptake increased significantly by increasing the nitrogen fertilizer level to 144-kg N/ha. Higher agro­nomic efficiency (kg rice/kg nitrogen applied) was found when rice was grown after legume crops and fertilized with 96 kg N/ha. The study con­cluded that 96 kg N/ha was the optimum and economical dose for rea­sonable productivity of Giza 177 when grown after legume crops and 144 kg N/ha if grown after non legume crops.