Working group session:
Functional Genomics
Presentation type:
poster
Authors:
Tang, Shiyi; Zhang, Zhengsheng; Teng, Zhonghua; Liu, Dajun; Zhang, Jian; Fang, Xiaomei; Liu, Dexin
Presenter:
Tang, Shiyi
Correspondent:
Abstract:
Cotton fiber quality traits are controlled by multiple genes of minor effect. Identification of significant and stable quantitative trait loci (QTLs) across environments and populations lays foundation for marker-assisted selection (MAS) for fiber quality improvement and studies of its molecular regulation. Here, a detailed genetic map is constructed and QTLs are detected based on an intraspecific recombinant inbred line population (RIL) derived from a cross between upland cotton ‘Yumian 1’ and ‘7235’. A total of 25,313 SSR primer pairs, including 5,000 developed from G. raimondii BAC-end sequences, were used to construct the genetic map which finally contained 1540 loci, spanning 2812.6 cM, with an average of 1.83 cM between adjacent markers. The population showed 662 distorted loci with more distorted loci located on the Dt subgenome (582) and favored Yumian 1 alleles (629). Fiber quality data were collected across four years. Variance analysis showed that fiber quality traits were significantly affected by both genetic and environmental factors. Significant correlations were also detected among fiber quality traits. A total of 62 QTLs， including 18 significant QTL were identified for five fiber quality traits with combined analysis and single environment analysis. Among these QTL, 12 were detected for fiber length, 14 for fiber uniformity, 13 for fiber micronaire, 11 for fiber elongation, and 11 for fiber strength. These QTLs explain phenotypic variation from 5.0% to 28.1%. For each trait, favorable alleles were conferred by both parents. Seventeen QTL were detected in multiple environments including four, three and ten QTL detected in four, three and two years respectively. QTL for different traits co-locate on Chr. 5, 8, 10, 18, and 24. The genetic map and stable QTLs are valuable for upland cotton genome research and breeding projects to improve fiber quality.