云南三种野生稻遗传多样性和系统进化研究

Study on Genetic Diversity and Phylogeny Evolution of Three Wild Rice Species in Yunnan

采用ISSR标记,对云南三种野生稻遗传多样性进行研究,并以竹类、栽培稻粳稻02428和籼稻金刚30以及非洲长雄野生稻为对照进行聚类分析,探讨云南三种野生稻遗传进化方向。结果表明,33条ISSR引物,在所有的材料中总共扩增出464个等位基因,平均每条引物扩增出多态性条带14.1条;从总体水平上看,云南三种野生稻具有丰富的遗传多样性,三种野生稻的多态位点数NP、多态位点百分率p、有效等位基因数Na、观察等位基因数Ne、Nei基因多样性指数H和香农指数I分别为357、76.74%、1.7694±0.4217、1.3391±0.3637、0.2037±0.1851和0.3180±0.2532;三种野生稻品种间基因分化系数Gst为0.5194,品种间的基因流Nm为0.4627,说明三种野生稻之间基因交流水平低,品种间存在较大的遗传分化。UPGMA聚类分析表明,在三种野生稻的进化过程中,疣粒野生稻分化最早,其次为药用野生稻,普通野生稻分化最晚。

The genetic diversity in lhree wild rice species and bamboo, cultivated rice and O. longistaminata were assessed, and compared by ISSR method to determine their phylogenetic relationships, discuss the evolution direction of three kinds of Yunnan wild rice. The results indicated that a total of 464 alleles were detected among all the materials by 33 strips of ISSR primers, 14.1 polymorphic bands were amplified of the average of each primer. Rich genetic diversity existed in the three wild rice species at the aggregate level. The number of polymorphic loci（Np ）, the percentage of polymorphic loci（p ）, the effective number of alleles（Na）, observed number of alleles（Ne）, Nei ＇s genetic diversity index （H） and Shannon index （I） were 357, 76.74%, 1.7694±0.4217, 1.3391±0.3637, 0.2037±0.1851 and 0.3180±0.2532. The coefficient of gene differentiation （Gst） was 0.0968 among the three wild rice species while the gene flow （Nm） was 0.4627, which shown that the gene exchanged at low level among three wild rice species and the genetic divergence was relatively high among rice varieties. UPGMA cluster analysis revealed the evolutionary process of three wild rice, O. meyeriana differentiats first, following by the O. Officinalis, O. rufipogon differentiats at the latest.