东南亚62个籼型水稻亲本SSR遗传多样性分析

Analysis of Genetic Diversity of 62 Indica Rice Parents From Southeast Asia Based on Microsatellite Marker

为探讨东南亚水稻亲本间的遗传多样性,以东南亚62份籼型水稻亲本为材料,选择29对水稻功能基因标记以及平均分布于12条染色体、多态性较高和条带清晰的72对SSR引物进行遗传多样性和聚类分析。结果表明,32对多态性引物在62份水稻材料中检测到201个等位基因,每个位点等位基因数（Na）变异范围为2-12,平均为6.281;有效等位基因数（Ne）变异范围为1.067-5.399,平均为2.867;多态信息含量（PIC）变异范围为0.061-0.789,平均为0.515;平均Shannon信息指数（I）为1.176,变幅为0.143-1.908;观察杂合度（Ho）为0.977,范围为0.936-1.000;期望杂合度（He）为0.439,范围为0.179-0.937;固定指数（Fis）的范围为0.882-1.000;基因流（Nm）的范围为0-0.0157。聚类分析表明,在遗传相似系数为0.805处,东南亚水稻亲本被分为6大类,同一国家大多数品种聚为一类。相对于普通分子标记,功能基因标记的平均等位基因数不高,其遗传多样性参数也低于普通分子标记,东南亚各国水稻品种间的亲缘关系较近,遗传多样性程度较低。研究结果为水稻育种亲本选配、新种质资源的创制以及杂种优势利用等提供了科学依据。

In order to provide molecular basis for the effective utilization of germplasm resources,the genetic diversity and cluster analysis of 62 indica rice parents from Southeast Asia were discussed by 29 functional gene markers reported as well as 72 conventional SSR markers with rich polymorphism,clear band pattern,and well-distributed in 12 chromosomes. The results showed that 6 functional markers and 26 SSR markers were polymorphic,the percentage of polymorphic loci was 20. 7% and 36. 1%,respectively. The total number of alleles were 201 and averaged 6. 281 per locus with a range from 2 to 12. The number of effective（ Ne） ranged from 1. 067 to 5. 399 with a mean value of 2. 867.The polymorphism information content（ PIC） ranged from 0. 061 to 0. 789 with a mean value of 0. 515. The Shannon＇s information（ I） indices varied from 0. 143 to 1. 908 with an average value of 1. 176. The observed heterozygosity（ Ho）ranged from 0. 936 to 1. 000 with an average value of 0. 977. The expected heterozygosities（ He） ranged from 0. 179 to0. 937 with an average of 0. 439. UPGMA clustering analysis showed that the 62 indica rice parents from southeast asia could be divided into six groups at a genetic similarity coefficient of 0. 805,most of materials from the same country were organized into a big or small category. Compared to the conventional molecular markers,the average number of alleles per locus and the genetic diversity parameter values of functional gene markers was lower. Rice varieties from different countries had a close genetic relationship and a deficiency of genetic diversity,it was indispensable to broaden the genetic basis of rice varieties from southeast asia. The results would provide a scientific evidence for parents selection,creating new germplasm resources and exploitation of heterosis in rice breeding.