大豆种质资源遗传多样性及开花期性状分析OA

[Objective]This study aimed to systematically analyze the genetic diversity and the genetic basis of flowering time traits in soybean germplasm resources,identify germplasm with complementary flowering time and genetic backgrounds,and provide a theoretical basis for improving ecological adaptability and molecular design breeding in soybean.[Methods]A total of 294 soybean cultivars and intermediate germplasm accessions were used as materials.Whole-genome sequencing was performed using the 180K gene chip.Population structure and the heritability of flowering time were analyzed through principal component analysis,cluster analysis,genetic distance and genetic similarity calculations,combined with a kinship matrix.[Results]The flowering time of the 294 soybean accessions ranged from 36 to 69 days,with a mean of 41 days,a coefficient of variation of 15.688%,and a heritability of 0.42.After quality control,71 880 SNPs were obtained.Principal component analysis showed that PC1 and PC2 cumulatively explained 12.05%of the phenotypic variation.Cluster analysis divided the 294 accessions into three major groups,with Group I further subdivided into four subgroups,and it contained 261 accessions,while Groups II and III were smaller but exhibited significant genetic differentiation.Genetic distance analysis revealed that genetic distances among accessions ranged from 0.000 578 to 0.491 218,with an average of 0.249 783.Genetic similarity analysis showed that the average genetic similarity among accessions was 0.745 1.The difference in flowering time between accessions with the largest and smallest genetic distances was 24 and 8 days,respectively,and significant differences in flowering time were observed among groups.[Conclusion]The 294 soybean germplasm accessions exhibit rich phenotypic variation in flowering time and moderate heritability,with a clear population genetic structure.Some groups retain unique gene pools and show significant genetic differentiation from mainstream cultivars.These findings provide important data support and a theoretical basis for mining flowering time-related genes,selecting parents based on genetic complementarity,and directionally improving the ecological adaptability of soybean.