Phenotypic principal component and cluster analysis were carried out on agronomic characters of two Yunnan plateau japonica rice backbone parents( Dianyu 1 and Todorokiwase) and their derivative varieties. The results showed that:( 1) There were no significant differences in panicle length,flag leaf angle,flag leaf width and seed setting rate between two backbone parents compared to others agronomic characters.( 2) There were also no much differences in agronomic characters among derivative varieties from t...