Preliminary experiment on the rational regulation of early rice nitrogen fertilizer under preceding winter potato planting

This experiment was carried out to study the rational regulation of early rice nitrogen fertilizer under preceding winter potato planting. Field experiments were conducted to compare the effects of different application levels of nitrogen fertilizer on early rice yield when the winter potato was proper preceding crop. The yield of early rice when nitrogen fertilizer was 60 kg/hm2 was significantly higher than 90 kg/hm2 and 120 kg/hm2, and has stronger lodging resistance. The nitrogen agronomic efficiency and nitrogen partial factor productivity were highest with the pure nitrogen of 60 kg/hm2. The yield of early rice was increased significantly by organic fertilizer application. Therefore, it is suggested that the proper application of organic fertilizers and reducing the amount of using nitrogen fertilizer by 70%-80% in early race growth when winter potato were proper preceding crop, were beneficial to increase the yield, utilization rate and economic benefits.