| Twelve upland cotton varieties were used to make NCII crossing to study the inheritance of fiber quality traits, a F2:3 family, derived from the cross between the two upland cotton varieties: Bar19/1 and Acala 1517-77, was used to construct SSR and AFLP marker linkage map and to map the quantitative trait loci(QTL) controlling fiber quality traits.The major results in this study are as follows:1. The heredity of fiber quality traits were mostly additive. Except fiber uniformity, others have a higher heritability. Fiber uniformity should be selected in high generation. The mid-parent heterosis of fiber quality traits in 12 F1 hybrid were analyzed. The result showed that fiber quality in F1 generation was about equal to the average of its parents and the heterosis is not obvious.2. Total 494 pair of SSR and AFLP primers were used to select polymorphic markers from Bar19/1 and Acala 1517-77. There are 113 pairs of primers with polymorphism between the two parents, 93 pairs of primers were used to screen the F2 individuals, which produced 93 Mendelian segregation markers. Using MAPMAKER/EXP 3.0b (the min LOD is 3.0 and the max genetic distance is 50 cM.), a genetic map was constructed which contain 70 markers and 22 linkage groups covering a genetic distance 670.8 cM.3.The normal distribution test for 5 fiber quality traits segregated in F2:3 was performed, the result showed that all appeared normal distribution. The composite interval mapping (CIM) method was used to analyze the quantitative trait loci (QTLs) of fiber quality traits based on F2:3 family, 5 QTLs of fiber quality traits were identified,which include one for fiber length, four for strength and one for micronaire, located in linkage group 1,3,4 and 7, respectively. The four of five QTL fiber quality could explain 4.5%, 12.42%, 12.64% and 20.56% of the phenotypic variation, respectively. In addition, one QTL of fiber strength appeared positive effect in low value parent, explaining 17.36% of the phenotypic variation.
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