Quantitative Inheritance of Yield and Its Components in Upland Cotton (Gossypium hirsutum L.) Cultivars with Varied Lint Percentages
Improving cotton yield is still the main goal of present cotton breeding; it is meaningful for studying the genetics of cotton yield traits for yield breeding. Lint percentage is one of the important yield components, and plenty of data show that the raising of cotton yield has close relation with lint percentage improvement. At the same time, the different levels of correlation is exist between lint percentage and other yield traits, yield components and fiber quality characters. Therefore, the inheritance re-search of lint percentage and its related traits is very important. In this paper, major-polygene jointing generations analyses were first combined with diailel cross experiment analyses to investigate the genetics of yield and its components in upland cotton (Gossypium hirsutum L.) at single and whole gene levels, respectively, by making crosses using cultivars with different lint per-centages. Joint analyses of six generations were performed in the genetics of yield traits in two high×low lint percentage crosses, using the method of major gene-polygene mixed inheritance model. The major genes controlling each of yield traits were always detected at least in one cross, indicating that the major genes controlling yield Waits existed generally. The comparison of major gene and polygene heritability for all traits between two crosses showed major gene heritability had more stable tendency than polygene heritability. Heritability proportion of each Wait was different between two crosses. Lint percentage, boll weight and seed index were mainly controlled by major gene and polygene in the two crosses, respectively; seed yield and lint yield were mainly controlled by major gene in the two crosses; lint index was mainly controlled by polygene in cross Ⅰ and belonged to typical poly-gene inheritance in cross Ⅱ; bolls per plant belonged to typical major gene inheritance in cross Ⅰ and was mainly controlled by polygene in cross Ⅱ. The diallel cross results indicated that yield and its components of upland cotton had always higher variance of major genetic effects, and the yield traits were controlled by additive effects and dominant effects altogether. In which, lint percentage and lint index were mainly controlled by additive effects; seed yield, Boll weight and seed index were mainly con-trolled by dominant effects; lint yield and bolls per plant were mainly controlled by additive effects and dominant effects. Both common broad heredity and common narrow heredity of lint percentage and lint index were always the highest, which had also the highest average value of total heritability in joint generations analyses. Among yield components, bolls per plant had the most contribution to lint yield, the second contribution from lint percentage, and the least contribution from boll weight. Our studies might provide some theoretical foundation for further elucidating the heredity rule and inheritance mode of major gene-polygene of yield and its components in upland cotton, as well as for adopting appropriate breeding strategy to improve cotton yield.
国家科技期刊平台
NSTL
万方数据
维普
