Analysis of morphological diversity and classification of hybrids F_2 of core collection of rice landrace in Yunnan province

To solve the problems of narrow hereditary basis and conquer difficulties in application of local rice landrace, 498 strains of F2 were chosen as material, after hybriding 548 strains of Yunnan rice core idioplasm with Yunnan mainly-cultivated indica rice, Diantun 502(Oryza satica), and with combination line 35(Oryza satica) from japonica rice and indica rice, morphological diversity of hybrid generations of Yunnan rice core idioplasm was identified and classified in terms of japonica rice and indica rice and rice land area.The result showed that:1) The morphological diversity of hybrid F2 was high among accessions assessed,and its seed-setting rate, filled grain no.per panicle, unfilled grain no.per panicle, peduncle length presented a great morphological genetic variation,in acldition,its average diversity index was also high.2) The variation trend of single characters is consistent between indica and japonica and rice cropping region; there was a great difference on diversity index among characters. 3) Through a cluster analysis, the material could be divided into 4 class groups with different characters in which differences in shape character was obvious. It would be advantageous to the breeding choice.