基于ISSR标记的稻属AA基因组遗传多样性分析

为了确定稻属AA基因组物种间的遗传差异和系统进化关系,62份来自广泛地理分布的水稻品系被用于ISSR标记分析。这些品系包含有6个野生稻种(O.nivara,O.rufipogon、O.barthi,O.longistaminata,O.glumaepatula,和O.meridionalis)和2个栽培稻种(O.sativa和O.glaberrima)。21条能产生良好重复性条带模式的ISSR引物被筛选出,并在62个水稻品系中揭示出非常好的多态性。全部样品的基因多样性为0.527,同时显示出ISSR标记在稻属物种遗传多样性研究中具有强大的作用。根据ISSR条带模式,利用Jaccard配对相似系数构建的一致性树状图,显示出具有良好自展支持率的稻属AA基因组遗传多样性关系。结果表明,来自不同大陆的稻属物种具有较近的亲缘关系,尤其是亚洲野生稻物种与Vaughan1989年建立的稻属分类系统具有良好的一致性。研究结果将对稻属AA基因组野生稻在水稻育种实践中的有效利用具有非常重要的意义。

ANALYSIS ON GENETIC DIVERSITY OF AA-GENOME ORYZA SPECIES BY ISSR MARKERS

In order to determine genetic d!versity of the AA-genome Oryza species （Poaceae）, inter-simple sequence repeat （ISSR） markers from a total of 62 rice accessions collected worldwide were analyzed. These accessions encompassed six wild （O. nivara, O. rufipogon, O. barthiL O. longistaminata, O. glumaepatula, and O. meridionalis） and two cultivated （O. sativa and O. glaberrima） species. 21 selected ISSR primers that produced consistent and repeatable banding patterns revealed significant polymorphisms among the 62 rice accessions with an overall gene diversity （DG） of 0.527, indicating the power of 1SSR markers in studying genetic diversity in Oryza germplasm. The consensus tree constructed on the basis of the pairwise Jaccard similarity coefficients of the ISSR banding pattern revealed an evident genetic variation relationships of the AA-genome Oryza species with high bootstrap value supports. It is concluded from this study that the Oryza species from different continents possessed close linkages and current classification of the AA-genome Oryza species suggested by Vaughan （1989） remains valid, particularly in relation to that of the Asian wild rice. The knowledge will be useful for the effective utilization of AA-genome wild Oryza species in rice breeding programs.