title: Mapping quantitative trait loci for seed size traits in soybean (Glycine max L. Merr.).
abstract: Seed size traits in soybean--length, width and thickness--and their corresponding ratios--length-to-width, length-to-thickness and width-to-thickness--play a crucial role in determining seed appearance, quality and yield. In this study, an attempt was made to detect quantitative trait loci (QTL) for the aforementioned seed size traits in F(2:3), F(2:4) and F(2:5) populations from the direct and reciprocal crosses of Lishuizhongzihuang with Nannong 493-1, using multi-QTL joint analysis (MJA) along with composite interval mapping (CIM). A total of 121 main-effect QTL (M-QTL), six environmental effects, eight environment-by-QTL interactions, five cytoplasmic effects and 92 cytoplasm-by-QTL interactions were detected. Fifty-two common M-QTL across MJA and CIM, 21 common M-QTL in more than two populations and 5 M-QTL in all three populations showed the stability of the results. Five M-QTL had higher heritability, greater than 20%. In addition, 28 cytoplasm-by-QTL and 4 environment-by-QTL interactions were confirmed by CIM. Most M-QTL were clustered in eight chromosomal regions. Our results provide a good foundation for fine mapping, cloning and designed molecular breeding of favorable genes related to soybean seed size traits.
authors.affiliation: Section on Statistical Genomics, State Key Laboratory of Crop Genetics and Germplasm Enhancement, College of Agriculture, Nanjing Agricultural University, 1 Weigang Road, Nanjing, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Xu
authors.forename: He-Nan
authors.initials: HN
authors.lastname: Li
authors.forename: Guang-Jun
authors.initials: GJ
authors.lastname: Li
authors.forename: Xia
authors.initials: X
authors.lastname: Wang
authors.forename: Li-Guo
authors.initials: LG
authors.lastname: Cheng
authors.forename: Yuan-Ming
authors.initials: YM
authors.lastname: Zhang
mesh_terms: D002874:Chromosome Mapping / Q000379:methods*; D032461:Chromosomes, Plant / Q000235:genetics; D003593:Cytoplasm / Q000235:genetics; D004777:Environment; D008040:Genetic Linkage; D009929:Organ Size / Q000235:genetics; D010641:Phenotype; D040641:Quantitative Trait Loci / Q000235:genetics*; D019655:Quantitative Trait, Heritable; D012639:Seeds / Q000033:anatomy & histology* / Q000235:genetics*; D013025:Glycine max / Q000033:anatomy & histology* / Q000235:genetics*