Working group session:
Structural Genomics
Presentation type:
oral
Authors:
Xiaomei, Fang; Zhengsheng, Zhang; Jian, Zhang; Dajun, Liu; Zhonghua, Teng; Xueying, Liu; Xiaoqin, Wang; Shiyi, Tang; Dexin, Liu
Presenter:
Xiaomei, Fang
Correspondent:
Zhengsheng, Zhang
Abstract:
Cotton is a leading fiber crop worldwide and it is important to dissect QTL controlling fiber quality traits. Fine-mapping QTLs and identifying molecular makers closely-linked with fiber quality traits will enhance the marker-assisted selection breeding (MAS) and the identification of the candidate genes underlying the favorable traits. Stable QTL controlling fiber strength, elongation and micronaire with overlapping intervals have been identified on Chromosome 7 in upland cotton F2 and RIL populations from a cross (CCRI 35 × Yumian 1) in our previous studies. To fine map these QTL, a fine mapping F2 population with 2484 individual plants from a cross between recombinant line RIL014 and CCRI 35 was established. For RIL014, the QTL region on Chromosome 7 derived from Yumian 1 whereas the other region derived from CCRI 35. A total of 1062 SSR primer pairs were designed from chromosome 1 of G. raimondii genome corresponding to the QTL region. Twenty-eight polymorphic primer pairs were used to test genotype of the fine-mapping population and a local genetic map of QTL region was constructed. The local map spaned 13.3 cM and contained 28 loci, which shared synteny with their putative physical position on chromosome 1 of G. raimondii genome. Based on the fiber quality traits data collected from fine mapping population, three QTL controlling fiber quality traits were mapped to a same interval of 0.9 cM (SWU2678-SWU2707), and these QTL explained the phynotypic variation from 5.1% to 11.7%. The QTL region corresponded a 735-kb physical interval on chromosome 1 of G. raimondii, and contained 25 genes.