Study on Interactive Effects of Fertilizer and Density on Yield and Yield Components of Rice in Cold Area

To investigate the effects of multiple factors on yield and yield components of rice,including nitrogen fertilizer dosage at different stages,application time of regulating fertilizer(RF) and hill spacing(HS),and field experiment with multiple factors quadratic rotational-regressive-orthogonal combination design was conducted in cold area of China.The conventional japonica rice variety kengjiandao 10 was used.The results showed that the experimental factors had both single-factor effect and interaction effect on yield.N-fertilizer at earlier stage(ES),amount of N-fertilizer of panicle-fertilizer and application stage of regulating fertilizer(RF) had significant effects on yield and the effect of the interaction of the first two factors on yield was just next to ES;the effect of hill spacing(HS) on yield was not significant;proper increase of N-fertilizer at earlier stage(ES) could improve effective panicle then ensure high yield.Finally,we can control yield and yield components and obtain high yield by coordinating relationship of N-fertilizer at earlier stage(ES) and the amount of N-fertilizer of panicle-fertilizer.