INDICA-JAPONICA DIFFERENTIATION IN CHINESE RICE LANDRACES

Ninety Chinese rice landraces were examined with special reference to the indica-japonica differentiation in terms of traditional criteria, isozyme analysis and PCR analysis of the chloroplast DNA (cpDNA). Cult ivars were separated into indica and japonica defined by a discriminan t function (Z) based on key characters, as well as by isozyme genotype s. Most indica landraces had chloroplast DNAs with a deletion at the P st-12 fragment, while most japonica landraces had cpDNAs without the d eletion. Two traditionally recognized varietal groups in China, keng a nd hsien, corresponded largely to the respective japonica and indica r evealed in our study. The results obtained in this study showed good a greement for classification of indica and japonica types by the three methods: discriminant analysis by Z value, isozyme analysis, and PCR a nalysis for cpDNA.