QTL mapping of fiber quality in an elite hybrid derived-RIL population of upland cotton

Abstract

Xiangzamian 2 (XZM2) was the most widely cultivated cotton hybrid planted as F 1 hybrids and as selfed F 2 seeds in China before the release of transgenic Bt hybrids. By crossing two parents of XZM2, Gossypium hirsutum cv. Zhongmiansuo12 (ZMS12) and G. hirsutum acc. 8891, and through subsequent selfings, we obtained F 8 and F 9 populations of 180 recombinant inbred lines (RILs). A RIL population was cultivated in two cotton-growing regions in China for 2 years. The purpose of the present research was to detect quantitative trait loci (QTL) for fiber quality and provide information applicable to cotton breeding. A genetic map was constructed mainly using SSR markers. QTL controlling fiber quality traits were determined at the single-locus and two-locus levels, and genotype-by-environment interactions were analyzed. Among the main-effect QTL, a fiber length QTL qFL-D2-1 and a reflectance QTL qFR-D2-1 were simultaneously detected at two growing regions in 2 years, which suggested a high degree of stability in different environments, and might be of particular value for a marker-assisted selection (MAS) program. The results suggested that epistatic effects, as well as additive effects, of QTL play important roles in fiber quality in these RILs. In our research, the phenomenon of QTL clusters was detected in the cotton genome. Keywords Main-effect AE Epistatic-effect AE QTL AE Fiber quality AE Clusters Abbreviations AFLP Amplified fragment length polymorphism EST Expression sequence tag QTL Quantitative trait locus/loci RAPD Random amplified polymorphic DNA RIL Recombinant inbred line SRAP Sequence-related amplified polymorphism SSR Simple sequence repeats

Construction of a linkage map and QTL mapping for fiber quality traits in upland cotton (Gossypium hirsutum L.)

“…Here we found many common characteristics of QTLs related to fiber quality traits as described in the previous reports involving interspecific maps [3,10,23,[33][34][35][36][37][38] and intraspecific maps [12,15,26,30,[39][40][41][42][43][44][45][46], although few common markers were used in the present research and the previous studies, and the maps covered different region parts of cotton genome, making it difficult to compare the common QTLs, some QTLs were detected and mapped on the same chromosomes and affect common traits. These include seven QTLs for fiber length located in the same chromosomal regions as reported earlier [10,26,34,41,42], two QTLs for fiber uniformity ratio located in the same chromosomal regions [43,46], two QTLs for fiber micronaire [10,43,44], three QTLs for fiber elongation [30,36,42,43,46,47], and 4 QTLs for fiber strength [26,34,36,43,44,46,47].…”

“…These include seven QTLs for fiber length located in the same chromosomal regions as reported earlier [10,26,34,41,42], two QTLs for fiber uniformity ratio located in the same chromosomal regions [43,46], two QTLs for fiber micronaire [10,43,44], three QTLs for fiber elongation [30,36,42,43,46,47], and 4 QTLs for fiber strength [26,34,36,43,44,46,47]. For example, the chromosome regions where QTLs were detected for fiber length in our research matched those in an interspecific map developed from an F 2 population [10]; the QTLs may be common QTLs for fiber quality traits.…”

QTL ANALYSIS OF FIBER COLOR AND FIBER QUALITY IN NATURALLY GREEN COLORED COTTON (Gossypium hirsutum L.)

“…Transgressive segregations exceeded Nazilli-84 in L, and both parents in a, b, ∆a, ∆b and ∆E values. There are transgressive segregations reported in fiber related traits in the literature (Wang et al, 2006;Shen et al, 2007;Qin et al, 2008;Luan et al, 2009;, which were consistent with our current results. It has been also demonstrated that F 2 hybrids can exhibit superior performance for agronomic and fiber traits when compared with their parental lines (Gutiérrez et al, 2002).…”

“…This could be due to either limited marker coverage or having no detectable QTL on the linkage groups. However, similar results regarding this issue were reported in previous studies Wang et al, 2006;He et al, 2007;Wu et al, 2009). …”

Genetic Mapping in Cotton

“…Mapping populations are obtained using two contrasting parents for the desired trait. In self-pollinated crops; usually mapping populations include F 2 [56,57]; F 2:3 [58,59], recombinant inbred lines (RILs) [60,61], backcross (BC) [62,63], Backcross inbred lines (BILs) [64], near isogenic lines [65,66], doublehaploids [67,68], chromosome substitution lines (CSILs) [69,70]. F 2 , BC, RILs and doublehaploids have been highly used for linkage mapping studies in cotton.…”