基于野生大豆回交群体挖掘大豆叶形性状遗传位点OA

To identify and enrich genetic loci regulating soybean leaf shape traits,three wild soybean backcross populations consisting of 168 lines in total were developed using the cultivated soybean cultivar Jidou 12 as the recurrent parent and wild soybean ZYD2738 as the donor parent in this study.Phenotypic differences in leaf shape between the two parents,phenotypic variation and genetic analysis of leaf shape across populations,and QTL mapping for soybean leaf shape were performed to mine genetic loci and dissect the genetic mechanisms underlying soybean leaf shape.Phenotypic variation and genetic analyses revealed that compared with ZYD2738,Jidou 12 exhibited significantly increased left leaf length,middle leaf length,right leaf length,left leaf width,middle leaf width and right leaf width by 399.59%,374.94%,431.53%,576.39%,531.90%and 567.42%,respectively(P<0.001).The left leaf angle of Jidou 12 was significantly smaller,accounting for 86.77%of that of ZYD2738(P<0.01).Except for leaf angle,the heritability of all other leaf shape traits was higher than 0.55.Two-way ANOVA showed that the F-values of environment,genotype and genotype-by-environment interaction(G×E)for soybean leaf shape traits ranged from 0.13 to 5 556.15,5.97 to 19.11,and 4.90 to 21.33,respectively.These results indicated that environment,genotype and G×E interaction all exerted significant effects on soybean leaf shape traits across the two environments(P<0.001).Physical fingerprint maps of the three wild soybean backcross populations were constructed based on resequencing technology,with 997,996 and 990 molecular markers detected in populations 14006,14008 and 14022,respectively.A total of 47 QTLs associated with leaf shape were identified,with LOD scores ranging from 2.50 to 5.45 and the phenotypic variation explained ranging from 11.53%to 32.20%.Among these,three novel co-localized genetic loci governing soybean leaf shape were newly identified.Analysis of additive effects demonstrated that the functional genes of Locus4_2 and Locus17 were derived from Jidou 12,while Locus9_1 originated from ZYD2738.In conclusion,this study provides valuable genetic resources and foundational data for the exploration and utilization of wild soybean germplasms,as well as further investigations into the genetic regulatory mechanisms of soybean leaf shape.