Effect of rice straw return plus nitrogen fertilizer on growth and development, yield and quality in rice.

The effects of straw return plus nitrogen fertilizer on growth and development,yield and quality in rice were studied.In comparison with the rice-straw removal treatment,the rice-straw return treatment reduced the plant height,dry matter weight,chlorophyll content and leaf area index during growth transition period,whereas no significant differences between both the treatments were observed during the heading period and the grain-filling period.There were no significant differences in yield components (grain filed,Panicles and 1000-grain weight) except the spikelets per panicle and seed-setting rate between the two treatments.The rates of brown and milled rice increased while chalky rice rate and chalkiness decreased in the rice-straw return compared with those in the rice-straw removal treatment.Rice –straw return with 9t hm2 increased both the protein and amylose contents,which resulted in the decline of cooked rice quality.