Effects of Density and Nitrogen Application Rate on Population Structure and Yield of Early-maturing Late Japonica Tongjing 981

The study adopted split block design with different treatment levels of density and fertilizer to investigate the growth period,population tiller dynamics,leaf area,dry matter accumulation,plant traits,panicle-grain structure,yielding ability and stress resistance of Tongjing 981 under different density and nitrogen fertilizer levels,so as to make clear the effects of different densities and nitrogen fertilizer levels on the population development and yield of Tongjing 981.The results showed that a too-low density was not conductive to the formation of sufficient number of panicles,and when the density was too high,it affected the number of grains per panicle and 1000-grain weight;and when nitrogen fertilizer was at a too-low level,it would restrict the population development,and a too-high nitrogen fertilizer easily led to the extension of the growth period and the aggravation of sheath blight.Reasonable density and fertilization level could make the development of individuals in Tongjing 981 population coordinated,and further help to establish a reasonable population structure,maintain a high leaf area and dry matter accumulation during the filling period,and balance the relationship of population dry matter weight with economic coefficient and panicle,grain and weight,thereby improving the population quality and yield of Tongjing 981.