我国早熟陆地棉品种遗传多样性分析

Analysis of Genetic Diversity of Early Maturing Upland Cotton Varieties in China

【目的】研究早熟陆地棉种质遗传多样性,为北疆早熟陆地棉育种提供理论依据。【方法】基于43个早熟陆地棉品种表型和基因型数据,利用Power Marker V3.25软件,进行遗传多样性分析。【结果】长江流域环境下,新疆棉区与我国其他棉区育成的品种,在早熟性相关表型性状上差异不显著;西北内陆环境下,二者之间则差异显著。另外,174对具有稳定多态性的SSR引物用于分析43个品种的遗传多样性,共检测到486个等位变异位点,每对引物的等位变异为2-7个。等位基因变异的多态信息含量（PIC）在0.044-0.750 0。分子检测表明：新疆棉区育成的品种遗传基础较狭窄。利用Power Marker V3.25软件计算的遗传距离进行聚类,43个参试品种以遗传背景、育成单位、地理来源等聚为8类。【结论】与其他棉区品种相比,新疆早熟棉区育成的品种,其早熟性相关性状遗传基础狭窄,表型性状的遗传多样性受环境影响较大。聚类图反映了不同系统品种之间的交叉以及早期和近代早熟陆地棉不同系统之间的融合现象。

【Objective】The research aims to study genetic polymorphism of early maturing upland cotton germplasm and provide a theoretical basis for its breeding in Northern Xinjiang. 【Method】Phenotypic and genotypic data of 43 early maturing upland cotton varieties were used to analyze their genetic diversity. 【Result】In the environment of the Yangtze River Drainage area,there was no significant difference in the earliness related traits between varieties bred in Xinjiang cotton planting region and those bred in other cotton-planting region in the country. However,in the environment of northwest inland Valley,there was significant difference in the earliness related traits between these varieties. 174 pairs of SSR primers were used to analyze the genetic diversity of 43 early maturing upland cotton varieties mentioned above. The primers had 486 alleles,with allelic variation of 2-7 per primer pair; and the polymorphic information content（ PIC） was around 0. 044 to0. 7500. The results of SSR markers indicated that the Xinjiang＇s cotton varieties that we tested possessed littlegenetic diversity. The Nei＇s genetic distance and the category of accessions were calculated using Power Marker V3. 25 software. The 43 germplasm resources could be categorized into eight major groups with genetic background,breeding units and geographical origin.〗Conclusion〗It was indicated that gearmplasm resources of Xinjiang early maturing cotton remained with a relatively low level of genetic diversity. And the genetic diversity of the phenotypic traits were obviously influenced by the environment. The clustering figure reflected the fusion cross between the system source varieties as well as between different systems of early and modern precocious upland cotten.