云南水稻传统品种内的遗传多样性及其维持机制初探  

Preliminary Studies on the Within-varietal Genetic Diversity and Its Maintenance of Traditional Rice from Yunnan

作　　者：董树斌[1] 卢宝荣[2] 王云月[1] 杨慧[1] 涂敏[1] 李林[1] 

机构地区：[1]云南农业大学植物保护学院,农业生物多样性应用技术国家工程研究中心,云南昆明650201 [2]复旦大学生命科学学院,生物多样性研究所,上海200433

出　　处：《云南农业大学学报（自然科学版）》2010年第1期1-9,共9页Journal of Yunnan Agricultural University:Natural Science

基　　金：国家重点基础研究发展计划(“973”项目)(2006CB100205)

摘　　要：为了探讨云南水稻传统品种内不同样本群体间的遗传多样性及其空间分布,以及空间隔离和种子介导的基因流在水稻传统品种遗传多样性的维持过程中的作用,利用24对微卫星(SSR)引物,对来自云南不同地区和村寨的6个水稻传统品种66个不同样本群体的共660份样本进行了遗传多样性和遗传关系的分析。结果表明,24个SSR位点共检测到133个等位基因,都为具有中度或者高度多态的位点,期望杂合度(He)为0.662,平均多态信息含量(PIC)为0.615,表明云南水稻传统品种具有较高水平的遗传多样性。分子方差(AMOVA)分析的结果表明云南水稻传统品种的遗传变异主要发生在地区内样本群体间(58%),地区间为(31%),样本群体内具有为11%的遗传多样性。品种间和地区间有一定水平由种子介导的基因流(Nm)。聚类分析表明,66个水稻样本群体在遗传距离为1.1水平上分为两大类,基本上相同的品种聚在一起,地理来源相近也聚在一起,但有些品种有明显的地区间交叉。Mantel检验的结果表明,每个品种样本群体的之间遗传距离和空间距离不具相关关系,揭示出云南水稻传统品种群体内的遗传多样性现状可能是其环境异质性、空间隔离、种子介导的基因流综合作用的结果。To investigate genetic diversity and its spatial distribution, as well as the mechanism for maintenance of genetic diversity via spatial isolation and seed-mediated gene flow in traditional rice varieties, we analyzed a total of 660 rice plants representing 66 sample populations of 6 traditional varieties from different regions and villages in Yunnan Province for their genetic diversity and genetic relationships, using 24 microsatellite loci. Consequently, a total of 133 alleles were detected from the 24 SSR primer pairs, with medium or high polymorphisms for the SSR loci. The gene diversity as meas- ured by the average expected heterozygosity （ Hc） was 0. 662 and the polymorphism information con- tent （PIC） of all samples was 0. 615, indicating high level of genetic diversity of in rice traditional varieties in Yunnan. The AMOVA indicated that about 58% of genetic variation was detected among varieties within regions, 31% of variation among regions, and 11% of variation within sample populations. This suggested a certain level of seed-mediated gene flow （ Nm） among sample populations of different varieties and among regions. Cluster analysis showed that the 66 rice sample populations could be divided into two major groups at the genetic distance coefficient of 1.1. In principle, the sample populations belonging to the same variety and having close spatial distance were grouped together, although there are some overlaps of the sample populations. Mantel test demonstrated no evident correlation between genetic distances and spatial distances of the sample populations of each variety. This study suggested that the current status of genetic diversity among rice populations in Yunnan Province could have resulted from the combined effects including environmental heterogeneity, spatial isolation, and seed-mediated gene flow via famers＇ seed exchange between and within regions.

关 键 词：水稻 传统品种 遗传多样性 遗传距离 空间分布 基因流 

分 类 号：S511.03[农业科学—作物学]