湟水流域梨种质资源遗传多样性分析OA

[Objective]The study aimed to explore the genetic diversity of local pear species germplasm resources in Qinghai Huangshui Basin and provide a theoretical foundation for promoting the identification and rational and effective utilization of local pear germplasm resources.[Method]Twenty-nine pear germplasm samples collected from five cultivation areas in the Huangshui Basin were used as objects,and 22 phe-notypic traits(13 descriptive phenotypic traits and 9 quantitative characters)were observed.Combined with SSR molecular markers,the ge-netic diversity of pear species germplasm resources in the Huangshui Basin was analyzed.[Result]The diversity of quantitative characters(0.963)was richer than that of descriptive phenotypic traits(0.915)in germplasm resources through diversity index analysis.Principal component analysis indicated that the cumulative contribution rate of 7 principal component factors reached 78.812％,with the morphological characteristics of floral organs and leaf shape being the main identification morphological indicators in phenotypic traits.A total of 85 alleles were detected using 11 SSR molecular markers with an average polymorphic information content(PIC)of 0.576,which could effectively re-veal the genetic diversity of these resources.The average Shannon's index(I)of twenty Qinghai local varieties was 0.840 and the PIC was 0.420,indicating relatively rich genetic diversity among local varieties.Cluster analysis showed that the pear germplasm resources in the Huangshui Basin mainly included four categories:Pyrus ussuriensis,P.bretschneideri,P.sinkiangensis and P.communis,and the other three types were local native varieties except for P.communis.There was a certain relationship between the phenotypic differences among varieties and the cultivation environment.Among the local varieties,P.sinkiangensis had a closer genetic distance to P.communis,while P.ussuriensis and P.bretschneideri had a farther genetic distance from P.communis.[Conclusion]The pear germplasm resources in the Huangshui Basin,especially the local varieties of Qinghai,exhibit rich genetic diversity.It is recommended to strengthen the identification,conservation,and de-velopment of Qinghai local pear germplasm resources.