海南三种野生稻遗传多样性的比较研究

利用39对SSR引物对海南114份普通野生稻、146份疣粒野生稻和81份药用野生稻进行扩增，从多态位点比率、平均等位基因数、香农指数等多个指标比较了3种野生稻遗传多样性的差异。结果表明，普通野生稻的遗传多样性最高，疣粒野生稻次之；在所检测的53个位点中，药用野生稻和疣粒野生稻的多态位点数分别为普通野生稻的1/7和2/7，等位基因数分别为普通野生稻的37%和39%；平均每个位点的实际杂合度，以普通野生稻杂合度最高（60%），分别是疣粒野生稻和药用野生稻的4.6倍和6.6倍。Wright-统计量和聚类分析结果表明,普通野生稻群体的遗传多样性主要来自群间，当遗传一致度I等于0.53时，3个居群分别属于不同类群,因此建议将3个普通野生稻居群都纳入原生境保护点建设范围。同时，药用野生稻和疣粒野生稻无论居群间还是居群内遗传变异都很小，各居群个体间出现部分交叉，只有当I大于0.9时才分别聚为不同的类群，因此，在进行原生境保护时只需保护遗传多样性水平高的居群即可。

Genetic Diversity of Three Wild Rice Species in Hainan Province

The genetic diversity of three wild rice species in Hainan, China, was comparatively analyzed with 39 selected SSR markers which evenly distributed throughout rice genome and normally amplified bands in all three wild rice species. The results indicated that total 210 alleles were detected with 39 SSR primers. Polymorphic loci were 97.44% in Oryza rufipogon and 23.08% and 15.38% in O. meyeriana and O. officinalis respectively. Based on the related parameters, Oryza rufipogon showed the highest genetic diversity and O. officinalis maintained the lowest one. For instance, the percentage of polymorphic loci (P) and the mean number of alleles (A) per locus in O. officinalis were only 1/7 and 37% of those in O. rufipogon while those in O. meyerian were 2/7 and 39% of those in Oryza rufipogon respectively. Similarly, the average observed heterozygosity of O. rufipogon was the highest, which was 4.6 and 6.6 times of that of O. meyeriana and O. officinalis respectively. Wright's F-statistics showed that the genetic variations within and among O. rufipogon populations were rather high, but those of both O. officinalis and O. meyeriana were very low, meaning that both individuals and populations of O. rufipogon have much different genetic backgrounds and those of the other two species have similar genetic backgrounds. The UPGMA clusters also showed that the three populations of O. rufipogon clustered into different groups at the point of I=0.53, while the populations from the other two species grouped only after I=0.9 or more. Similarly, the individuals within each population of O. rufipogon showed different genetic backgrounds with a few exceptions, but a lot of individuals in each population of both O. officinalis and O. meyeriana had the same genetic background. Considering above results, all tested populations of O. rufipogon and those with the highest genetic diversity of the other two species should be conserved with an in situ approach. O. meyeriana and O. officinalis should be conserved with only several individuals sampled in each population.