利用表型性状构建杜仲雄性资源核心种质

Establishment of Male Core Collection of Eucommia ulmoides Based on Phenotypic Traits

以306份杜仲雄性种质为试验材料,通过测量杜仲雄花和叶片等相关的22个表型性状,从遗传距离、取样方法、取样比例、聚类方法 4个层次探讨了构建杜仲雄性资源核心种质的最佳取样策略。应用均值差异百分率(MD)、方差差异百分率(VD)、极差符合率(CR)和变异系数变化率(VR)4个参数来检验各取样策略的优劣。通过比较核心种质和原始种质的表型多样性指数、符合率和主成分,对构建的核心种质进行代表性检验。结果表明:"多次聚类优先取样法+10%的取样比例+马氏距离+最短距离法"取样策略最佳,其均值差异百分率、方差差异百分率、极差符合率和变异系数变化率分别为0%、86.36%、100%和157.62%。核心种质的最终取样比例为10.8%。核心种质与原始种质22个表型性状上的多样性指数t检验结果不显著。核心种质与原始种质在22个指标上的均值符合率在92%~100%之间,最大值、最小值符合率为100%,多样性指数符合率在89%~100%之间。原始种质和核心种质的前10个主成分相同,累积贡献率分别为84.834%和90.422%。获得的33份杜仲雄性种质能够代表306份原始种质的表型变异特征。

306 male germplasms of Eucommia ulmoides were used as test materials.Through the measurement of22 related phenotypic traits,such as male flowers and leaves of E.ulmoides,we discussed the optimum sampling strategy to construct core germplasm resources of male E.ulmoides from four aspects of genetic distance,sampling method,sampling proportion and clustering method.The sampling strategies were tested by the value of MD,VD,CR and VR.By comparing the phenotypic diversity index,coincidence rate and principal component of the core and original germplasm,the core collection was tested by representativeness.The results showed that the optimal strategy was：multiple cluster priority sampling method ＋10% sampling proportion ＋mahalanobis distance ＋minimum distance method.The value of MD,VD,CR,VR were 0%,86.36%,100% and 157.62%,respectively.The final sampling proportion of core germplasm was 10.8%.The diversity index of 22 phenotypic characters of core germplasm and original germplasm was not significant by t test.The average coincidence rate between the core germplasm and the original germplasm on the 22 indexes was between 88.89%-100%,the maximum and minimum coincidence rate was 100%,and the diversity index coincidence rate was between 88.55%-98.54%.Thetop ten principal comp onents from the original germplasm and core germplasm were identical,and the accumulative contribution rates were 84.834% and 90.422%,respectively.The obtained male core collection of 33 E.ulmoide could satisfactorily represent the phenotypic variation characteristics of 306 E.ulmoide germplasms.