Objective  Genetic diversity and phenotypes of 140 newly introduced Oryza sativa Japonica were studied and organized for germplasms collection and breeding selection.

Method On the 140 germplasms, 10 phenotypic traits were classified by variations on distribution, types, genetic diversity, correlation, clustering, and principal components.

Results  With a few exceptions, the 10 phenotypic traits was mainly intermediate type ranging 6.87-36.86% on the coefficients of variation. The panicle count was the highest and the grain length the lowest types; while the effective panicle count the greatest and the grain shape the least on genetic diversity index that varied from 1.87 to 2.07. The number of panicle grains of the germplasms correlated positively with the entire growth period, plant height, and panicle length, but negatively with the effective panicle rate and setting rate. Significant differences in the phenotypic traits were found of the Japonica rice in 5 taxa varying in numbers for each taxon reflecting a rich genetic diversity. Four principal components in the phenotypes accounting for 77.42% of total were extracted. The top 10 germplasms with the highest comprehensive evaluation D values were Dangyu 5, Okumura Xue, Zhongdafei, Zhonghua 15, Yunleng 22, BG1, Nonghuhe, Bigeng 42, Xingtu, and G Zhenshan 9713.

Conclusion TenJaponica rice germplasms with desirable overall agronomic traits and yield potential were selected from 140 varieties for a broadened collection.