基于SSR标记构建西南玉米地方品种核心种质的方法

Methods of constructing a core collection of maize landraces in southwest China based on SSR data

结合地方品种的地理起源和种质特性,以17%的抽样率选取玉米核心品种,用SSR分子标记技术对54个玉米地方品种进行遗传聚类,研究中国西南地区玉米地方品种核心种质的构建方法.结果表明,由9个核心品种构成的核心种质较好地保持了原玉米地方品种群体的遗传变异,42对SSR引物在原玉米地方品种群体和核心种质中分别检测到268、256个等位基因,平均多态信息量分别为0.76和0.73,其评价参数平均数百分率、方差百分率和变异系数可变率分别为10%、10%、83.5%,表明构建的核心种质能较好地代表原种质资源群体.

According to their geographic origins and germplasm characteristics, 54 maize landraces were clustered genetically on the basis of SSR data. The core landraces were selected with a 17 percentage of sampling and sampling strategies were investigated to construct a core collection of maize landraces in southwest China. The results showed that the core collection composed of 9 maize landraces retained a large variation in the initial collection. 268 and 256 polymorphic alleles were detected in the initial collection and the core collection, respectively by 42 pairs of SSR primers. Mean polymorphism information content in the initial collection （0.76） was a little higher than that in the core one （0.73）. Estimates of the evaluating parameters MD, VD and VR were 10%, 10% and 83.5%, respectively suggesting that the core collection constructed was the optmal one representing the initial collection.