黑龙江省大豆种质遗传结构及遗传多样性分析

Genetic Structure and Diversity of Soybean Germplasm in Heilongjiang,China

利用22个表型性状和60个微卫星(simple sequence repeat,SSR)位点对黑龙江省140份代表性种质(78份地方品种和62份育成品种)进行分析,根据UPGMA(unweighted pair group method with arithmetic mean)和Model-base对SSR数据进行遗传结构划分。结果表明,参试品种可分为2大类群,第Ⅱ类群的各项多样性指标均高于第I类群,2个类群遗传距离为0.2427;PCO结果显示这2个类群在不同区域,这与地理来源和育成年代密切相关。依据品种类型分为育成品种和地方品种两组,后者的各项多样性指标均高于前者,两组间的遗传距离为0.1131。依据表型数据的PCO分析表明,分布区域与品种类型有关,与SSR结构分类的结果吻合度低,两组品种主要在3个主成分的6个表型性状上有所不同。它们不是2个相对独立的遗传群体,根据分子标记和表型分类各有特点;建议在种质遗传多样性研究中将分子数据和表型数据结合起来。

Heilongjiang province is the main production area for soybean （Glycine max） in China, having the high genetic diversity of cultivated soybean. It is useful for breeding and production in the region to develop new germplasm. The aim of this study was to reveal genetic structure and genetic diversity of spring sowing soybean germplasm from Heilongjiang, and provide a reli- able strategy in soybean breeding program. A total of 140 accessions of soybean cultivars including 78 landraces and 62 developed cultivars were investigated using 60 microsatellite（simple sequence repeat, SSR） markers and 22 phenotypic traits. All accessions were grouped into two clusters based on SSR with UPGMA and Model-base. The results showed that genetic diversity of cluster Ⅱ was higher than that of cluster Ⅰ, Nei＇s genetic distance was 0.2427 between two clusters. PCO （principlal co-ordinate） analysis revealed that two clusters distributed in different regions, which was closely related to the geographic origin and breeding years. All accessions were also divided into two groups （developed cultivars and landraces） based on variety types, genetic diversity of the landraces was higher than that of developed cultivars. Nei＇s genetic distance was 0.1131 between two groups. The PCO figure based on the phenotypic genetic similarity index matrix clustered 140 cultivars into developed cultivars group and landrace group. The ftrst principal component reflected main seed coat color; the second one mainly depended on growth period and ma- turity data. There were obvious differences on the three principal components, which were composed of six phenotypic characters, between developed group and landraces group, which were not independent genetic clusters. The results indicated that there was abundant genetic diversity in Heilongjiang spring sowing soybeans. Thus the optimal strategy combined SSR data and agronomic traits is necessary for genetic diversity analysis of soybean germplasm.