The Effects of Nitrogen Fertilizer Application on the Nitrogen Absorption,Dry Matter Accumulation and Yield of Super High-yielding Rice Luliangyou996

By the measures of different fertilization methods and different ratios of basal,tillering and panicle fertilizers,the characteristics of nitrogen absorption and its effects on the dry matter accumulation and yield of super high-yielding rice Luliangyou996 were discussed.The results show that Luliangyou996 is a high-yielding rice cross which needs much nitrogen fertilizer and has strong dry matter accumulation ability.In order to get high yield(7.5 t/hm2),high dry matter production(13.0 t/hm2) and high harvest index(0.53),yield components should be improved to achieve high efficient panicles(270.0×104 panicles/hm2),large number of grains per panicle(no less than 120 grains) and high seed set(above 90%).Along with the increase of nitrogen application,the benefit of nitrogen fertilizer of Luliangyou996 declines and the nitrogen amount for one hundred kilogram of grain rises.Over application of nitrogen fertilizer in the prophase,influences the nitrogenous absorbability and accumulation in the postphase.The total nitrogen demand is about 165~225 kg/hm2 when the grain yield is more than 7.5 t/hm2,but the grain yield is the highest when the nitrogen application is 195 kg/hm2.The proportion of basal and tillering fertilizer should be about 70% when the total nitrogen is less than 165 kg/hm2 and it should decrease to 60% when the total nitrogen is more than 165 kg/hm2.In general,50~60 kg/hm2 nitrogen is appropriate for panicle fertilizer.