基于EST-SSR标记的古槐遗传多样性评价及群体结构分析OA

This study employed EST-SSR molecular markers to evaluate the genetic diversity of ancient So-phora japonica populations,analyze their population structure,and elucidate genetic relationships among them.The aim is to provide a scientific basis for selecting high-quality germplasm and to inform conserva-tion strategies for ancient trees.Genetic diversity was assessed using 16 EST-SSR molecular markers across 91 samples from six populations.AMOVA was performed to determine the level of genetic differen-tiation,while STRUCTURE,PCoA and UPGMA analyses were used to reveal the genetic structure of pop-ulations.Results indicated that the EST-SSR molecular markers amplified a total of 90 alleles,demonstra-ting a moderate to high level of genetic diversity(I=1.056,H=0.572,He=0.571).AMOVA revealed that 95%of genetic variation occurred within populations.The mean interpopulation genetic differentiation coefficient Fst was 0.046,indicating low genetic differentiation.Consistently,the STRUCTURE,PCoA,and UPGMA analyses grouped the six populations into three distinct subpopulations.In summary,the studied ancient Sophora japonica populations exhibit relatively high genetic diversity.Sustained and effective gene flow exists between them,and no significant inbreeding depression was observed overall.The WF popula-tion shows the highest genetic diversity and warrants full protection and rational utilization;the BJ and ZB populations exhibit a slight heterozygote deficiency and lower genetic diversity,necessitating timely conser-vation efforts.