[Objective] The study aimed to compare the difference of organ morphology and yield composition in 10 rice cultivars with 3 sowing date,and to correlate leaf length and plant height with exogenous variables like temperature accumulation and sunshine duration.[Method] Detailed data of organ morphology and yield component were obtained and analyzed through repeated field observations and destructive samplings over the growing season,including leaf length,node number,tiller number,plant height and grain yield of 10 rice cultivars（Takanari,IR72,Sankeiso,CH86,IR65564-44-2-2,Nipponbare,Takenari,Banten,WAB450-1-B-P-38-HB,Wuxiangjing 9） with 3 sowing dates（May 11,May 22,and June 19,2002）.[Result] Max leaf length for each node increased at the early growth stage and decreased at the later growth stage.The leaf length of CH86 and Banten was the maximum in 4 Indica cultivars and 6 Japonica cultivars,respectively.Node number and plant height decreased with the later sowing date,and that of CH86 was the maximum.The maximum grain yield was found in Wuxiangjing 9,and the greatest genotypic variation existed in rice yield,panicle number,spikelet per panicle,and grain weight;the grain yield ranged from 4 358 to 7 443 kg ha-1;the panicle number ranged from 158×104 to 330×104 ha-1;no direct correlation between yield,tiller number and plant height was observed in this experiment.[Conclusion] Empirical regression fitting of the resulting data was developed for leaf length and plant height prediction and yield component comparison,which could be used to construct deeper and more mechanistic models or to optimize rice growing conditions.
