Evaluation Of Alkaline Tolerance And Analysis Of Genetic Diversity In Japonica Rice

Using 378 japonica rice germplasms from 14 foreign countries and 13 provinces of China, the dead leaf rate under different alkaline stress was evaluated, and japonica rice germplasms with strong alkaline tolerance were slected. The results showed that the dead leaf rate under alkaline stress for pH9.4 was significantly larger than that under alkaline stress for pH 8.9, while alkaline stress for pH 8.9 was more suited to evaluate the dead leaf rate for japonica rice germplasms. The alkaline tolerance among different japonica rice germplasms from different geographical origins under alkaline stress for pH8.9 was significantly different. The japonica rice germplasms from Australia, Italy and Jiangxi province of China were appeared lower dead leaf rate, which had stronger alkaline tolerance than others. The dead leaf rate of tested materials when 16 days to 26 days under alkaline stress for pH8.9 were ranged from 20%to 100%, and which showed continuous distribution near normal with larger variance and coefficient of variation. So this period was considered fit to evaluate the alkaline tolerance for japonica rice germpalsms. Twenty one japonica rice germplasms, such as YR196, Baru, Fengjin, Nipponbare, 8068, Suijing 5 and so on with strong alkaline tolerance were selected, which showed stronger alkaline tolerance with less than 40% of the dead leaf rate when 16 days under alkaline stress for pH8.9. These germplasms could be applied for further rice alkaline tolerance breeding.Japonica rice outstanding variety has certain genetic differences,60 pairs of SSR marker. Altogether discovers 311 alleles, the mean value is 5.18, the only three pairs have surpassed 10; The major allele frequency mean value is 0.7369, and the genotype mean value is 6.28,the observed heterozygosity mean value is 0.0041,and PIC mean value is 0.3365. But the heredity multiplicity performance is not very rich, than compares with the Japonica rice landrace. Beijing and Yunnan gene diversity is richest between the different country provinces of china, Australian and USA gene diversity is richest between the different countrys. The rule of cluster was obviously demonstrated that varieties from province or country.The north variety and south variety is separated in China.Between the different country of continent basic respectively gathers is a kind, Genetic relationship among varieties was correlated with geographical location.