| The Richards equation was used to fit grain filling processes of 3 transgenic (BADH) rice genotypes-52-7,51-15,51-22, theirs parents-Zhonghua 8(ck1)and Israeli upland rice-Baizhenzhu(ck2)under dry cultivation. The results revealed that the filling characteristics of grains at different positions were asynchronous type. In comparison with Zhonghua 8, the transgenic rice enhanced the filling rate of both the superior and inferior grains, elongated the active grain filling period and increased dry matter at the time reaching the maximum grain filling rate. Moreover, at the middle and late stage of filling, the difference in grain filling rate between the superior grains and inferior ones in the transgenic rice became smaller compared to Zhonghua 8. As a result, the transgenic rice had higher grain weight and less difference in grain dry matter between the superior grains and inferior ones than Zhonghua 8. Maximum grain filling rate, mean grain filling rate and dry matter at the time reaching the maximum grain filling rate were significantly and positively correlated to 1000-grain weight. |