Effects of Transplanting Density and Nitrogen Fertilizer Rate on Yield Formation and Grain Quality of Super High Yielding Rice Zhongzao 22

A field experiment was conducted with different transplanting densities (24,30 and 36 hills/m2) and nitrogen fertilizer rates (0,105,150 and 195 kg/hm2 N) by using a super high yielding indica rice,Zhongzao 22 as material. The transplanting densities had less effect on the seed setting rate,1000-grain weight,number of productive panicles,grain number per panicle and grain yield. The effect of nitrogen fertilizer rate on grain number per panicle was lower than that on the number of productive panicles,seed-setting rate and 1000-grain weight. Seed-setting rate and 1000-grain weight were decreased significantly at 195 kg/hm2 of nitrogen applied rate. The transplanting density had no significant effect on rice quality. The protein content of rice increased with the increasing transplanting density. The increase in nitrogen fertilizer rate improved milling and appearance quality of rice,as well as protein content.