陆地棉纤维品质性状主基因与多基因混合遗传分析

Analysis on the Major Gene and Multigene Mixed Inheritance of Fiber Quality Traits in Upland Cotton(Gossypium. hirsutum L.)

采用2个纤维品质表现高强的材料和黄河流域棉区的2个主栽抗虫品种配成2个组合,利用主基因与多基因混合遗传模型分析方法,对主要纤维品质性状进行5个世代联合分析。结果表明多数品质性状是由一个主基因和多基因控制。主基因遗传效应中,F2分离群体中,比强度的遗传效应最大,为14.36%和8.40%,其次是绒长性状,为9.51%和2.59%。F2:3中的主基因效应与F2接近。主基因显性效应很小,除纤维长度在一个组合中总显性效应(主基因显性效应+多基因显性效应)为较大正值外,其余三个性状在两个组合中均表现负值或接近于0,杂合状态下多数纤维品质性状表型值偏向中亲值或低亲值,分子标记研究也证明了这一点,所以棉花纤维品质性状单纯依靠表型选择效率低,需要依靠分子标记辅助育种对主栽品种进行品质改良。

Two crosses 9708x0-153 and 6177x0-212 were made among four parents, which included two parents with high fiber strength, 0-153 and 0-212, originating from crossing G. hirsutum L. with G. arboreum L., and backcrossing with G.hirsutum L as recurrent parent, and other two commercial transgenic varieties （9708 and 6177） with resistance to budworm. The results of joint analyses of multiple generations of P1,P2,F1,F2 and F2-3 of two crosses showed one major gene plus polygene mixed inheritance model in all fiber quality characters, except for fiber elongation. There were highest beritability of major gene for fiber strength, 14.36% and 8.40% in F2.The second highest heritability of major gene for fiber quality is fiber length, 9.51% and 2.59% in F2.But major gene effect were very little for other fiber quality traits, which indicated the beritability of polygene were prominent for fiber quality characters, 27.88%-50.42% in F2. Negative value or zero of major plus polygene dominant effects for three traits except for fiber length. Hence, mid-parents value or tendency to lower parent in F1 for most of fiber properties lead to low selection efficiency if only depending on phenotype, which indicated that molecular assisted selection should be applied in order to imvrove the fiber aualitv traits.