Abstract:

Field experiments were conducted to compare the effects of slow and controlled release fertilizer combined with straw returning on rice yield and nitrogen use efficiency. The results showed that the use of slow and controlled release fertilizer and urea-ammonium fertilizer to replace traditional compound fertilizer and urea, respectively, and straw returning to the field at the same time could improve rice yield and dry matter accumulation. The fertilization mode of slow and controlled release fertilizer + urea-ammonium fertilizer + straw returning had an effect on the improvement of nitrogen accumulation and nitrogen apparent efficiency. Under relatively reasonable nitrogen application conditions, the continued application of nitrogen fertilizer led to a decrease in crop yield and a decrease in the nitrogen apparent efficiency. In actual production, the fertilization mode of basic application of slow and controlled release fertilizer, top-application of urea-ammonium and straw returning can be promoted. However, in order to improve the nitrogen fertilizer use efficiency and reduce the loss of chemical fertilizer, the total nitrogen input of 667 m² chemical fertilizer should not be less than 12 kg, and 12-15 kg should be appropriate, so as to achieve high yield and efficient utilization of resources in late rice.

Key words: rice yield, slow and controlled release fertilizer, straw returning, nitrogen apparent efficiency