| A field experiment was conducted to investigate the effects of nitrogen(N) application on yield, biological and nutritional properties of castor in irrigated oasis area, with six N levels, including 0 kg·hm-2 (N0), 50 kg·hm-2 (N50), 100 kg·hm-2 (N100), 150 kg·hm-2 (N150), 200 kg·hm-2 (N200) and 250 kg·hm-2 (N250). The results showed that, (1) the best N application was 195 kg·hm-2, and it could produce the highest castor yield (8×103 kg·hm-2). (2) N application could promote biologi
cal character of castor e.g. plant height, stem diameter, number of ears. Main ear length, number of seeds, hundred-grain weight and yield of castor showed increase under appropriate N application (150 kg·hm-2 or 200 kg·hm-2). (3) At flowering stage, the accumulation of N and potassium(K) of castor plant increased with N application, with the rate of 150 kg·hm-2 having the largest effect on phosphorus(P). (4) There existed a positive relation between the rate of N application and the contents of leaf N and P. In addition, at filling stage, K in leaf was transferred to panicle, it suggested castor need abundant K at this stage. |