Characteristics of nitrogen distribution in rapeseed(Brassica napus L.) with different nitrogen utilization efficiency for grain production

In this study,73 and 98 conventional rapeseed(Brassica napus L.) cultivars were cultured in 2006-2007 and 20072008,respectively,to study the characteristics of nitrogen(N) accumulation and distribution by testing dry matter weight and the nitrogen content of different organs.The selected rapeseed cultivars were classified into 6 types based on their nitrogen use efficiency for grain production(NUEg) levels using MinSSw method.Results showed that differences of NUEg in different types were significant.With increasing of NUEg,the seed yield,N accumulation in seed and the ratio of N accumulation in seed to total nitrogen increased;while N accumulation in stem and branches and the ratio of nitrogen accumulation in stem and branches to total nitrogen reduced.N accumulation of shell and the ratio of shell to total nitrogen also were reduced.Improving NUEg could be achieved by selecting high NUEg cultivar and/or reasonable cultivation measures translocating more N to plant nutritive organs.