Effects of Nitrogen Application Ratio on the Growth and Yield of Rice(Oryza sativa. L)

Nitrogen fertilization is one of the important factors in the rice cultural regulation,which play an important role in the finally yield.To understand the effects of nitrogen application ratio,the two fertilization treatments used 9∶1(NT) and 6∶4(NP) ratios of N were applied at the pre-and post birth growth stage.At the same time,three different panicle types of rice were used as the experiment material.The results showed that the NP application treatment could be favorable to the rice growth as following: it could reduce the ineffective tillering,increase the effective spike rate,improve the population structure,delay the degradation of chlorophyll,increase the leaf area index of late growth stage and accelerate the transition of tem-sheath reserve to grain,which lead to the high yield of rice.The results also showed that effects of NP application treatment on final yield of large-panicles rice were more significant,which indicating that the appropriate increasing in N supply at late stage of large-panicles rice may play a more important role on the yield formation.