Study On Genetic Diversity Of Yunnan Glutinous Rice

The glutinous rice (Oryza sativa var. glutinosae) is the glutinosity type of rice variety that has high edible and economic value. Yunnan province is one of the richest Provinces on glutinous rice resource in China, as well as one of the origins and diversity centers of rice (Oryza sativa). In this report, the genetic diversity and structure of Yunnan glutinous rice varieties was analyzed by simple sequence repeat (SSR) markers. The Indica-Japonica differetiation was analyzed by insertion/deletion (InDel) markers and the rice blast resistance was studied by innoculation. The main results were as followings:1. Genetic diversity of 150 Yunnan glutinous rice varieties with 10 individuals per variety was analyzed by 24 SSR markers that are well distributed of 12 rice chromosomes. Totally 158 alleles were detected, all SSR loci were found middle or high polymorphic. The average polymorphism information content was 0.7262. The average effective allele numbers, Shannon's information index and expected heterozygosity were 4.5506, 1.5928 and 0.7642 respectively, which indicated abundant genetic variation of Yunnan glutinous rice. Analysis of molecular variance (AMOVA) indicated that about 86% and 14% genetic variation were detected between varieties and within varieties, respectively. Therefore, we need to protect more varieties to protect glutinous rice resources. The genetic diversity of glutinous rice varieties of south, southeast and southwest areas of Yunnan were significantly higher than that of central, northeast and northwest of Yunnan. The south, southeast and southwest Yunnan are genetic diversity centers of glutinous rice of Yunnan Province. These regions should be the hot spots of glutinous rice resource conservation. Cluster analysis showed the 150 Yunnan glutinous rice varieties contained abundant genetic variation with Nei's genetic similarity from 0.19 to 0.99 levels, but could not be classified into groups according to geographical regions.2. The Indica-Japonica classification and genetic variation of 60 glutinous rice varieties were done by 28 InDel markers and 24 SSR markers. The results showed that there were 24"typical Indica", 6"Indica", 2"Japonica"and 28"typical Japonica"varieties, respectively. By phylogeny analysis, principal component analysis and model-based structure analysis, the Indica and Japonica varieties could be separated obiously of glutinous rice. Genetic variation analysis showed the genetic diversity of Indica and Japonica glutinous rice were high, and the polymorphism difference were not significant. The analysis of molecular variance (AMOVA) indicated that 74% and 26% genetic variation were existed within and between subspecies of glutinous rice respectively with significant difference at 0.001 probability level.3. Rice blast resistance of 100 glutinous rice varieties was studied using 8 Yunnan rice blast pathogens by manual inoculation in greenhouse. The results showed the 64 varieties were over medium susceptibility and 34 varieties were medium susceptibility. Only 2 glutinous rice varieties were found to be susceptibility. Cultivated glutinous rice varieties were relative high disease resistant.