闽楠群体遗传结构分析与核心种质库构建OACSTPCD

[Objective]This study aims to provide a theoretical basis for scientific management,effective protection and efficient utilization of germplasm resources,by investigating population structure of collection germplasm resources of Phoebe bournei with SSR markers,and constructing a core collection of the germplasm resources.[Method]A total of 33 pairs of SSR primers were used to investigate the genetic diversity and genetic structure of 425 individual trees of P.bournei belonging to 218 subfamilies collected from 27 provenances of five provinces(autonomous region),including Fujian,Jiangxi,Hunan,Zhejiang,and Guangxi.Genetic diversity parameters such as number of observed alleles(Na),effective number of alleles(Ne),observed heterozygosity(Ho),Shannon's information index(I),Nei's diversity index(H)were calculated by combined DateTrans1.0 and Popgene32 software.The genetic structure of nine populations was analyzed using STRUCTURE 2.3.4 software.The core collection was constructed by using the method of grouping and stepwise clustering with the minimum distance.The genetic diversity parameters were examined by t-test,to verify the validity of the core collection for P.bournei.[Result]According to the geographical distribution of germplasm sources,218 families can be divided into 9 populations.A total of 130 alleles were detected at 33 SSR loci,and the average number of effective alleles(Ne)was 2.159,the average observed heterozygosity(Ho)was 0.224,the average expected heterozygosity(He)was 0.477,and the Shannon information index(I)average value was 0.841,indicating that there was the moderate genetic diversity in the germplasm resources of P.bournei.Genetic structure analysis classified nine populations into three groups.From the 425 original germplasm resources of P.bournei,85 core germplasms and 340 reserved germplasms were obtained through stepwise cluster sampling.The core germplasms accounted for 20%of the original germplasms,and the retention rates of its Na,Ne,Ho,He,I,and H were 92.318%,103.803%,116.652%,105.052%,103.341%,and 104.664%,respectively.The t-test analysis showed that there was no significant difference in the genetic diversity parameters between the core germplasm and the original germplasm,indicating that the core germplasm was able to fully represent the genetic diversity of the original germplasm.[Conclusion]The core germplasm collection preserves the genetic diversity information of the original collection,which removes the genetic redundancy.The results are beneficial to the effective protection and scientific utilization of P.bournei resources and lay a solid foundation for further breeding in P.bournei.