利用SRAP标记分析贵州砂梨资源遗传多样性

Genetic Diversity of Pyrus pyrifolia Resources in Guizhou Province Using SRAP Markers

采用SRAP标记技术,对贵州59份砂梨种质的遗传多样性进行分析。结果表明:(1)筛选的15对SRAP引物共扩增出151个位点,其中120个是多态性位点,多态百分率为79.47%。(2)POPGENE分析表明,贵州砂梨资源在物种水平上有效等位基因数(Ne)为1.355 9,Nei’s基因多样性指数(H)为0.216 9,Shannon’s信息指数(I)为0.336 2;在区域品种群水平Ne=1.261 1,H=0.155 5,I=0.235 2,以黔西南地区资源的遗传多样性最高,六盘水市最低。(3)聚类分析显示,在遗传相似系数0.75处,可将59份砂梨资源分为6个组,聚类分析结果具有一定的地理区域特性。研究认为,贵州砂梨种质具有较为丰富的遗传多样性,并表现出明显的地理区域特性;SRAP标记与ISSR标记在揭示贵州砂梨种质遗传多样性上具有高度的一致性,但SRAP标记能在更小的变异范围内揭示更多的遗传信息。

Genetic diversity and genetic relationship of 59 Pyrus pyrifolia germplasm resources distributed in Guizhou Province were analyzed using SRAP markers.The results showed that：（1）15SRAP primer pairs generated 151 bands and 120 presented polymorphic loci.（2）A relatively high level of genetic diversity was revealed by Ne（mean observed number of alleles）1.355 9,H（Nei’s genetic diversity）0.216 9,I（Shannon’s information index）=0.336 2at species level and by Ne=1.261 1,H=0.155 5,I=0.235 2at population level.Pear resource in Qianxinan Prefecture showed the highest genetic diversity and that in Liupanshui City showed the lowest.（3）Cluster analysis with UPGMA method showed that 59 P.pyrifolia germplasms could be grouped into six groups at genetic coefficient of 0.75.The result also indicated that P.pyrifoliaresources distributed in Guizhou Province had abundant genetic diversity with obvious geographical feature.The genetic diversity and genetic relationship of the P.pyrifolia germplasms could be revealed effectively by SRAP markers,which provided more genetic information in a smaller range of variation as compared to ISSR.