关键词: 大豆, 裂荚性, 全基因组关联分析, 遗传多样性, 作物驯化

Abstract:

Objective Investigating molecular mechanisms and germplasm resources of pod dehiscence resistance would provide evidence for uncovering the genetic and domestication mechanism of pod dehiscence resistance in soybean as well as accelerating the breeding of new soybean varieties with pod dehiscence resistance on southern China. Method With genome-wide association studies (GWAS) and genetic diversity analysis between wild and cultivated soybean populations, the genes related to soybean pod dehiscence habit were explored. The phenotype determination of 302 soybean varieties were conducted, and GWAS was performed using 95 ‍744 single nucleotide polymorphism markers in 2 years. And analysis of genetic diversity in QTL segment was carried, with the resequencing data of 1 308 cultivated soybeans and 203 wild soybeans. Result Through GWAS, three QTL loci that explained greater than 10% of the observed phenotypic variance were detected, namely qPdh-Chr08 (Gm08: 3048312), qPdh-Chr15 (Gm15: 312814), and qPdh-Chr16 (Gm16: 29951529). Among them, qPdh-Chr16 was known gene pdh1 (Pod dehiscence habit 1). Combining the resequencing data of wild and cultivated soybeans, it was found that there were population differentiation sequences caused by artificial selection in regions of qPdh-Chr08 and qPdh-Chr15. And two important candidate genes Glyma.08G038600 and Glyma.15G003600 were identified based on population differentiation sequences analysis. Through functional annotation, it was found that these two genes were involved in the metabolism of auxin and lignin, respectively. Conclusion Two new QTL loci qPdh-Chr08 and qPdh-Chr15 of soybean pod dehiscence habit were detected using two-year’s data. Differential genes between wild and cultivated soybean are identified within the QTL region, and two important candidate genes are ultimately identified.

Key words: soybeans, pod dehiscence habit, whole genome association analysis, genetic diversity, crop domestication