Localization of QTLs for yield and fiber quality traits of tetraploid cotton cultivar.

Using SSR and RAPD as molecular markers, and the 69 F2 families from a cross between Handan208 (Gossypium hirsutum) and Pima90 (Gossypium barbadense) as a mapping population, a linkage map comprising 126 markers was constructed. With an average spacing 13.7 cM between markers, the linkage map spanned 1,717.0 cM, which covers approximately 34.34% of the total recombinational length of cotton genome. Based on the linkage map and the F2:3 phenotypic data, overall genome QTL screening was conducted by composite interval mapping method, then 29 QTLs related to cotton yield traits and fiber quality traits were found. There are 16 loci related to yield traits and 13 loci related to fiber quality. Particularly, two QTLs relevant to fiber strength were detected, which could explain phenotypic variance of 34.15% and 13.86%, respectively.