Study on Nitrogen Fertilizer Application Effect with Different Plant Patterns in Reparian Rice Field

Using wheat-rice plant pattern as control, the nitrogen fertilizer application effect in rice field was studied with the pattern crop-riceand grass-rice in reparian area. The results show that under the condition of no nitrogen fertilizer and pure nitrogen fertilizer of 225 kg/hm~2, taking the rice field after wheat as CK, the yield in the rice field after shed crop increased 56.20% and 10.78%, and the net profit improved 95.39% and 14.49% compared with CK.But there was no obvious difference in the yield and net profit between the rice field after grass and after the wheat. With the different nitrogen levels in the rice field after shed crop, the rice yield, net profit, new net profit rate were the highest with the pure nitrogen fertilizer of 150 kg/hm~2, while the marginal cost reward rate, nitrogen agronomic efficiency, partial factor productivity were the highest with the pure nitrogen of 75 kg/hm~2. With the different nitrogen levels in the rice field after grass, the rice yield was the highest with the pure nitrogen fertilizer of 300 kg/hm~2, and the net profit, new net profit rate, marginal cost reward rate, nitrogen agronomic efficiency were the highest with the pure nitrogen fertilizer of 225 kg/hm~2, and the partial factor productirity was the highest with the pure nitrogen fertilizer of 150 kg/hm~2. In the rice field after the three crops, the quality difference shows mainly in the milling quality, amylose content and protein content with no nitrogen fertilizer, while in the milling quality, appearance quality and amylose content with the pure nitrogen fertilizer of 225 kg/hm~2.