摘要
【目的】利用SSR分子标记技术研究美洲黑杨种质资源的群体结构,构建美洲黑杨核心种质资源库,为美洲黑杨种质资源的科学管理、高效利用和有效保护提供理论依据。【方法】利用15对SSR引物,分析美洲黑杨6个种源23个采样点的338个个体的遗传结构。应用GeneAlEx 6.503等软件计算等位基因数(N a)、有效等位基因数(N e)、Shannon’s信息多样性指数(I)、观测杂合度(H o)、Nei’s遗传多样性指数(H)和多态信息含量(PIC)等遗传参数,并进行主坐标(PCoA)分析。采用分组的逐步聚类方法结合位点等位基因数目最大化法和位点稀有等位基因优先相结合的取样策略构建核心种质库,并在核心种质库的基础上补充种质个体使等位基因保留比例达到100.00%,形成优化核心种质库。通过对相关遗传参数的t检验和PCoA分析验证核心种质库和优化核心种质库的有效性。【结果】美洲黑杨群体结构研究结果表明6个种源群体被划分为3大类型,即分布在圣劳伦斯河流域的Que种源的个体和哥伦比亚河流域的Was种源个体归为一类;分布在密西西比河中下游流域的种源个体(Mis、Lou、Ten)大致归为一类;分布在密西西比河上游的Iow种源的个体单独分为一类。基于群体结构分组筛选出19份核心种质,占原始种质的5.62%,等位基因数的保留比例为79.83%,N e、I、H o、H、PIC遗传参数的保留比例分别为102.75%、103.39%、125.31%、104.72%和105.27%,通过t检验和PCoA分析表明核心种质库具有代表性。通过在核心种质库中添加包含缺失等位变异基因的15个补充种质,构建包括34个个体的优化核心种质库,取样比例为10.06%,等位基因保留比例为100.00%,其他遗传参数N e、I、H o、H、PIC的保留比例分别为107.94%、110.93%、119.48%、107.52%和109.19%,t检验和PCoA分析结果均表明优化核心种质库的遗传多样性与原始种质库之间没有显著差异,包含的遗
【Objective】SSR markers were employed for an analysis of population structure of a collection of germplasm resources of Populus deltoides,and a core collection of the germplasm resources was constructed in order to provide a theoretical basis for scientific management,efficient utilization and effective protection of germplasm resources of the species.【Method】The genetic structure of 338 individual trees of P.deltoides collected at 23 sampling sites of 6 provenances were analyzed using 15 pairs of SSR primers.Genetic diversity parameters such as number of alleles(N a),effective number of alleles(N e),Shannon’s information index(I),observed heterozygosity(H o),Nei’s diversity index(H),polymorphic information content(PIC)were calculated by GeneAlEx 6.503 and other software.And the principal coordinates(PCoA)analysis was also carried out.The core collection was constructed by using the method of grouping and stepwise clustering,combining with the method of maximizing the number of alleles and the sampling strategy of rare allele priority.More individuals were added in the core collection to capture 100.00%of the alleles forming an optimized core collection.The validity of the core collection and the optimized core collection was verified by t-test and PCoA analysis.【Result】The population structure showed that six provenances were divided into three types:the individuals originated from St.Lawrence River Basin(Que)and Columbia River Basin(Was)were classified as one group,while those from the middle and lower Mississippi River Basin(Mis,Lou,Ten)were classified as another group,and those of the Iow provenance from the upper Mississippi River were into one group.Based on the population structure,19 core germplasms were screened,accounting for 5.62%of the original collection,the retention rates of N a,N e,I,H o,H,PIC were 79.83%,102.75%,103.39%,125.31%,104.72%and 105.27%,respectively.t-test and PCoA analysis showed that the core collection was representative.By adding 15 individuals with missing alleles to
作者
陈存
丁昌俊
张静
李波
褚延广
苏晓华
黄秦军
Chen Cun;Ding Changjun;Zhang Jing;Li Bo;Chu Yanguang;Su Xiaohua;Huang Qinjun(State Key Laboratory of Forest Genetics and Tree Breeding Key Laboratory of Tree Breeding and Cultivation of National Forestry and Grassland Administration Research Institute of Forestry,Chinese Academy of Forestry,Beijing 100091)
出处
《林业科学》
EI
CAS
CSCD
北大核心
2020年第9期67-76,共10页
Scientia Silvae Sinicae
基金
中央级公益性科研院所基本科研业务费专项资金项目(CAFYBB2018SY007,CAFYBB2017ZA001-3)。
关键词
美洲黑杨
群体结构
核心种质库
Populus deltoides
population structure
core collection
