Abstract:

The low N use efficiency are not only resource-wasting, but also seriously impact soil, air, water and surrounding environments. This study aimed to clarify the application result of controlled-release nitrogen coated with polyethylene in supper-rice. With conventional nitrogen as control, the effect of super-rice yield, apparent N recovery rates and soil nutrients change long-term applying controlled-release nitrogen were determined through the fixed position experiments of controlled release nitrogen. The results showed that, the CRU 50%+PU 50% of rice yield reached the highest and rice yield reached 11200.5 kg/hm2. There was no significant difference between the CRU 50%+PU 50% and CRU 70%+PU 30%, but they were significantly higher than else nitrogen. The decreasing nitrogen treatment of applying controlled-release nitrogen were superior to common nitrogen as a base fertilizer and equivalent to common nitrogen as top fertilizer. The total content nitrogen of combined application of controlled-release nitrogen and common nitrogen could increase spike length, the number of grain per ear, filled grain number per panicle and 1000-grain weight. Nitrogen recovery of rice controlled-release nitrogen treatments were significantly higher than common nitrogen treatment. Nitrogen recovery of CRU 42%+PU 28% and CRU 70% were 53.73% and 52.06%, significantly over 8.90%-29.29% and 7.23%-27.62%, respectively. After harvest the soil nutrients were the most in 70% content nitrogen of controlled-release nitrogen. CRU 42%+PU 28% had notable effect on decreasing cost and increasing benefit, which provided a theoretical foundation for the application and promotion of controlled-release nitrogen fertilizer in super-rice.