野生稻与亚洲栽培稻的遗传多样性

为评价野生稻与亚洲栽培稻的遗传多样性及其变异关系，56对SSR引物被用于研究广泛地理分布的55份普通野生稻(其中32份O. rufipogon和23份O. nivara)和25份亚洲栽培稻(14份indica和11份japonica)样本。298个多态性位点被检出，占总扩增等位点的98.68%。野生稻多态性位点的百分比(平均达91%)及Nei’s遗传多样性值(h)明显高于亚洲栽培稻，表明普通野生稻比亚洲栽培稻具更丰富的遗传多样性。UPGMA聚类分析显示野生稻的两个类群(O. rufipogon和O. nivara)关系密切，但在遗传上存在明显的分化，支持其作为两个独立物种的分类观点。许多普通野生稻中籼粳分化尽管不很明显，然而亚洲栽培稻的籼粳亚种分化是明显的。亚洲栽培稻与多年生普通野生稻(O. rufipogon)关系更为密切，符合异源起源的遗传分化模式。

Genetic Diversity of Wild Rice and Cultivated Rice

To evaluate the genetic diversity and variation of common wild rice and Asian cultivated rice, 55 accessions of common wild rice (32 O. rufipogon and 23 O. nivara) and 25 cultivars of Asian cultivated rice (14 indica and 11 japonica) collected worldwide were analyzed by 56 SSR primer pairs. The polymorphic loci percentage was 98.68% and 298 polymorphic loci were detected. A comparison of the polymorphic loci percentage and Nei’s genetic diversity (h) indicated that the genetic diversity of common wild rice was obviously higher than that of Asian cultivated rice. The UPGMA cluster analysis revealed that there was a close relationship between O. rufipogon and O. nivara, but distinct genetic differentiation was detected between them, supporting the piont of view that they are two independent species. The results indicated that the indica-japonica differentiation was not very apparent in many wild rice whereas it was obvious in Asian cultivated rice. According to the cluster analysis, there was a closer consanguineous relationship between Asian cultivated rice and O. rufipogon, which supported the diphyletic origin hypotheses.