2021年12月9日 星期四
云南松材用种质保存库的构建策略及检验
Construction strategy and verification of timber-used germplasm conservation bank of Pinus yunnanensis
2019年 第28卷 第1期 页码[105-114]    下载全文[1.1MB]  
摘要


摘要: 为探讨云南松(Pinus yunnanensis Franch.)材用种质保存库构建的抽样策略并获得代表性子集,在其全分布区内选择26个代表性种群,每个种群选择30株样株组成原种质集,并选取18个表型性状测定值作为种质保存库的源数据。在此基础上,以地理种群分组,根据不加权类平均聚类分析结果进行取样;设定抽样比例分别为10%、20%、30%和40%,采用多样性指数法和改进的最小距离逐步取样法构建种质子集,并采用5个评价参数和主成分分析对不同抽样比例种质子集进行综合评价和确认。结果表明:各种质子集与原种质集18个表型性状的均值t检验均无显著差异;而40%、30%、20%和10%抽样比例种质子集分别有11、14、15和12个表型性状的方差总体上大于原种质集且差异显著,说明各种质子集表型性状的取值分散程度总体上大于原种质集。通过χ2检验,40%、30%和20%抽样比例种质子集与原种质集18个表型性状的频率分布均无显著差异,而10%抽样比例种质子集仅有2个表型性状的频率分布与原种质集分别存在极显著和显著差异。在原种质集和4个种质子集中,不同等级样株的分布频率基本相同,但随抽样比例降低,1级、9级和10级的样株比例逐渐增大,说明在构建种质保存库时,应适当增加极端样株的比例。4个种质子集各表型性状的Shannon-Weaver遗传多样性指数(H′)普遍高于原种质集,且随抽样比例下降H′值总体增大;其中,20%抽样比例种质子集与原种质集表型性状的H′均值存在极显著差异,30%和10%抽样比例种质子集与原种质集表型性状的H′均值存在显著差异。综合评价结果表明:10%、20%、30%和40%抽样比例种质子集均可代表原种质集,其中,20%抽样比例种质子集可客观地代表原种质集的表型遗传多样性,且该种质子集的5个评价参数值综合效应优于其他种质子集。主成分分析结果表明:按照20%抽样比例构建的种质保存库能够解释的表型遗传信息量大于原种质集,且既保留了大量分布外缘的样株,又减少了中心区域大量重叠的样株,据此确认20%抽样比例种质保存库可以作为云南松材用种质的代表性子集。

Abstract

To investigate sampling strategy for construction of timberused germplasm conservation bank of Pinus yunnanensis Franch. and acquire representative subsets, 26 representative populations were selected from its whole distribution area, and 30 sampling plants were selected from each population as an original germplasm set, meanwhile measured values of 18 phenotypic traits were selected as original data of germplasm conservation bank. On the basis, sampling was conducted according to the result of unweighted average cluster analysis by dividing groups of geographic population; setting sampling percentages of 10%, 20%, 30%, and 40%, respectively, germplasm subsets were constructed by using diversity index method and improved least distance stepwise sampling method, and 5 evaluation parameters and principal component analysis were employed to make comprehensive evaluation and confirmation of germplasm subsets with different sampling percentages. The results show that there is no significant difference in mean t-test of 18 phenotypic traits between each germplasm subset and original germplasm set; variances of 11, 14, 15, and 12 phenotypic traits in germplasm subsets with 40%, 30%, 20%, and 10% sampling percentages are generally greater than those in original germplasm set, and the differences are significant, indicating that scatter degree of phenotypic trait values in each germplasm subset is generally greater than that in original germplasm set. According toχ2-test, there is no significant difference in frequency distribution of 18 phenotypic traits between germplasm subsets with 40%, 30%, and 20% sampling percentages and original germplasm set, while there are extremely significant and significant differences in frequency distribution of 2 phenotypic traits between germplasm subset with 10% sampling percentage and original germplasm set. Among original germplasm set and 4 germplasm subsets, distribution frequencies of sampling plants in different classes are basically identical, but percentage of sampling plants in class 1, class 9, and class 10 gradually increases with the decrease of sampling percentage, indicating that percentage of extreme sampling plants should be increased appropriately when constructing germplasm conservation bank. Shannon-Weaver genetic diversity index (H′) of each phenotypic trait in 4 germplasm subsets is generally higher than that in original germplasm set, and H′ value increases in general with the decrease of sampling percentage; in which, there is an extremely significant difference in mean H′ value of phenotypic traits between germplasm subset with 20% sampling percentage and original germplasm set, and significant differences in mean H′ values of phenotypic traits between germplasm subsets with 30% and 10% sampling percentages and original germplasm set. The comprehensive evaluation results show that germplasm subsets with 10%, 20%, 30%, and 40% sampling percentages can represent original germplasm set, in which, germplasm subset with 20% sampling percentage can objectively represent the phenotypic genetic diversity of original germplasm set, and comprehensive effect of 5 evaluation parameters of this germplasm subset are better than that of other germplasm subsets. The principal component analysis result shows that germplasm conservation bank constructed with 20% sampling percentage can explain more phenotypic genetic information than original germplasm set, which reserves a lot of sampling plants distributed at the outer margin and reduces a lot of overlapping sampling plants in the center area, confirming accordingly that germplasm conservation bank constructed with 20% sampling percentage can be used as representative subset of timberused germplasm of P. yunnanensis.

关键词云南松; 材用种质保存库; 表型性状; 抽样策略; 表型遗传多样性
Key wordsPinus yunnanensis Franch.; timber-used germplasm conservation bank; phenotypic trait; sampling strategy; phenotypic genetic diversity
作者王晓丽1,2, 高成杰1, 李昆1
所在单位1. 中国林业科学研究院资源昆虫研究所, 云南 昆明 650224; 2. 西南林业大学林学院, 云南 昆明 650224
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基金项目中国林业科学研究院基本科研业务费专项(CAFYBB2017SY030)