亚洲不同生态区水稻群体遗传多样性与特异性分析

Genetic Diversity and Specificity of Rice Population in Different Asian Ecological Areas

研究不同生态区水稻群体的遗传多样性及其遗传结构分化、群体特异性及其相互关系,为水稻起源及亲本遴选提供遗传基础。选取均匀分布在水稻12条染色体上119对SSR标记,对440个品种进行全基因组扫描,利用PowerMarker 3.25和Structure 2.2进行遗传多样性和群体结构分析。在太湖流域水稻中检测到781个等位基因,平均多态信息含量(PIC)为0.52;在黑龙江水稻中检测到295个等位基因,PIC为0.25;在越南水稻中共检测到370个等位基因,PIC为0.30,这表明越南水稻和黑龙江水稻的多样性低于太湖水稻。特缺等位变异数最多的是黑龙江亚群(132),最少的是太湖亚群(4);特有等位变异数最多的是太湖亚群(284),最少的是黑龙江亚群(25)。从亚群间补充等位变异数来看,其补充等位变异数最多的是太湖亚群对黑龙江亚群的补充(447),最少的是黑龙江亚群对太湖亚群的补充(29)。利用Structure2.2软件将3个地区的440个品种分为7类血缘,发现每个血缘都不是独立的而是相互渗透的。不同生态类型水稻遗传背景既相互融合又相互补充,在品种培育上加以利用可拓宽育种资源。

Study on the genetic diversity, genetic structure, genetic specificity and the relationship of different rice populations in Asian ecological areas can provide genetic basis for exploring rice origin and selecting parental materials. 119 pairs of SSR markers which distributed in 12 chromosomes were selected, and the whole genomes of 440 rice cultivars were scanned. The genetic diversity and genetic structure were analyzed by PowerMarker 3.25 and Structure 2.2. A total of 781 alleles were produced in Taihu Lake rice cultivars and the PIC average value was 0.52. A total of 295 alleles were produced in Heilongjiang rice cultivars and the PIC average value was 0.25. A total of 370 alleles were produced in Vietnam rice cultivars and the PIC average value was 0.30. It indicated that the genetic diversity of Taihu Lake rice was higher than that of Vietnam and Heilongjiang rice. Heilongjiang rice population had the most specifically deficient alleles（132） and the Taihu Lake subpopulation had the least（4）. The Taihu Lake rice population had the most specifically existent alleles（284） and Heilongjiang rice population（25） had the least. The Taihu Lake subpopulation had the most complementary number of alleles（447） for Heilongjiang subpopulation. The Heilongjiang subpopulation had the least complementary number of alleles（29） for Taihu Lake subpopulation. The 440 varieties in the three regions were divided into seven germplasm groups by Structure 2.2, they were not independent but interpenetrating. The genetic background of rice cultivar populations in different Asian ecological areas has integration and complementation, which could widen the breeding resources.