黄灯笼辣椒核心种质资源比较构建研究

Comparative Study on the Construction of Capsicum chinense Jacquin Core Collection

核心种质的构建为种质资源的研究和有效利用提供了便利条件。以146份黄灯笼辣椒种质资源为试验材料,基于10个性状表型数据,采用混合线性模型分析方法无偏地预测基因型值,利用马氏距离计算种质间的遗传距离,分别采用2种取样方法(随机取样法和优先取样法),2种聚类方法(离差平方和法和类平均法),按照30%的抽样比率构建黄灯笼辣椒核心种质库。采用均值、方差、极差和变异系数4个指标评价不同取样方法和聚类方法构建核心种质库的优劣。试验结果表明,优先取样法优于随机取样法,类平均法优于离差平方和法。基于马氏距离、优先取样法、类平均法获取的43份黄灯笼椒核心资源能够代表原群体的遗传多样性。

Core collection construction facilitates the research and effective utilization of genetic resources. Taking 146 Capsicum chinense Jacquin germplasm as experiment materials, genotypic values of 10 traits were unbiasedly predicted through employing mixed linear model analysis method. The genetic distances among germplasm were calculated using Mahalanobis distance based on genotypic values. Core collections were constructed with 30% sampling proportion by using 2 sampling strategies （random sampling and preferred sampling） and 2 cluster methods （UPGMA and Ward＇s method）, respectively. The genetic variations among core collections were compared through evaluating the mean, variance, range and coefficient of variation of 10 traits. The results showed that preferred sampling method was better than the random sampling method; UPGMA was better than Ward＇s method. 43 core collections, obtained based on Mahalanobis distance, preferred sampling and UPGMA method, could represent genetic diversity of the initial collection. This study could provide important theoretical basis for efficient utilization of Capsicum chinense Jacquin germplasm and breeding of new varieties.