贵州旱稻种质资源的SSR遗传多样性分析

Genetic Diversity of Upland Rice Germplasm Resources from Guizhou Province Based on SSR Markers

本研究利用24对水稻微卫星(SSR)标记对源自贵州部分县乡种植以及早期基因库收集的112份地方旱稻材料的遗传多样性进行分析,结果共检出187个等位基因,每个位点的等位基因变幅为4～13个,平均Nei's基因多样性指数为0.6431,平均香农指数为1.3669。籼粳亚种均具有较高的遗传多样性,前者稍高于后者,但差异不明显。黔西南州拥有最多的种质,存在丰富的遗传变异,是贵州旱稻种质资源遗传多样性分布中心。分子方差分析表明,旱稻种质总变异的88%是由各地区内的群体间差异造成,地区间和各个群体内的遗传变异较小,均为6%。不同地区旱稻种质的遗传分化程度不一,变幅为2%～18%。聚类分析将供试旱稻材料较为明显地分为籼粳两个类群,而地理分组不明显。

The genetic diversity of 112 accessions of upland rice which collected from some counties of Guizhou province and from germplsam stock of Guizhou province were analyzed by using twenty-four pairs of SSR molecular markers in this research. 187 alleles were detected with the number of alleles （Na） per loci ranging from four to thirteen, mean Nei＇s genetic diversity index （He） and mean Shannon index were （Ⅰ） 0.643 1 and 1.366 9, respectively. Comparison of genetic changes in Na and He showed that the genetic diversity of indica subspecies slightly higher than that of japonica subspecies, but had no significant difference, both of the two subspecies had rich genetic diversity. The highest genetic variation was found in the southwestern prefecture of Guizhou province due to the abundant of genetic variation, and this area would be as the distribution center of genetic diversity of upland rice germplasm resources in Guizhou. The analysis of molecular variance （AMOVA） indicated that 88% of the variation was from differences among populations within regions, and only 6% of the variation was due to differences between regions, and 6% genetic variation within populations. The degree of the genetic differentiation of upland rice germplasm fluctuate from 2% to 18% according to the regions. Based on Nei＇s genetic identity, the 112 upland rice accessions could be classified into indica and japonica groups, but could not obviously be classified into groups according to geographical regions. This paper did provide the genetic information for distribution and genetic variation of upland rice germplasm in Guizhou, and thus laid a basis for conservation improvement and effective utilization of upland rice germplasm.