title: Quantitative trait locus analysis of agronomic and quality-related traits in cultivated peanut (Arachis hypogaea L.).
abstract: SSR-based QTL mapping provides useful information for map-based cloning of major QTLs and can be used to improve the agronomic and quality traits in cultivated peanut by marker-assisted selection. Cultivated peanut (Arachis hypogaea L.) is an allotetraploid species (AABB, 2n = 4× = 40), valued for its edible oil and digestible protein. Linkage mapping has been successfully conducted for most crops, and it has been applied to detect the quantitative trait loci (QTLs) of biotic and abiotic traits in peanut. However, the genetic basis of agronomic and quality-related traits remains unclear. In this study, high levels of phenotypic variation, broad-sense heritability and significant correlations were observed for agronomic and quality-related traits in an F 2:3 population. A genetic linkage map was constructed for cultivated peanut containing 470 simple sequence repeat (SSR) loci, with a total length of 1877.3 cM and average distance of 4.0 cM between flanking markers. For 10 agronomic traits, 24 QTLs were identified and each QTL explained 1.69-18.70 % of the phenotypic variance. For 8 quality-related traits, 12 QTLs were identified that explained 1.72-20.20 % of the phenotypic variance. Several QTLs for multiple traits were overlapped, reflecting the phenotypic correlation between these traits. The majority of QTLs exhibited obvious dominance or over-dominance effects on agronomic and quality traits, highlighting the importance of heterosis for breeding. A comparative analysis revealed genomic duplication and arrangement of peanut genome, which aids the assembly of scaffolds in genomic sequencing of Arachis hypogaea. Our QTL analysis results enabled us to clearly understand the genetic base of agronomic and quality traits in cultivated peanut, further accelerating the progress of map-based cloning of major QTLs and marker-assisted selection in future breeding.
authors: Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture, Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Wuhan, 430062, China.
authors: Li
authors: L
authors: Huang
authors: Haiyan
authors: H
authors: He
authors: Weigang
authors: W
authors: Chen
authors: Xiaoping
authors: X
authors: Ren
authors: Yuning
authors: Y
authors: Chen
authors: Xiaojing
authors: X
authors: Zhou
authors: Youlin
authors: Y
authors: Xia
authors: Xiaolin
authors: X
authors: Wang
authors: Xiangguo
authors: X
authors: Jiang
authors: Boshou
authors: B
authors: Liao
authors: Huifang
authors: H
authors: Jiang
mesh_terms: D010367:Arachis / Q000235:genetics*; D001947:Breeding; D002874:Chromosome Mapping / Q000379:methods*; D018744:DNA, Plant / Q000235:genetics; D008040:Genetic Linkage; D005819:Genetic Markers; D018745:Genome, Plant; D018895:Microsatellite Repeats; D010641:Phenotype; D040641:Quantitative Trait Loci; D019655:Quantitative Trait, Heritable
chemical_list: D018744:DNA, Plant; D005819:Genetic Markers