大麦蛋白质含量的遗传研究

Genetic Studies of Grain Protein Content in Barley

由六个亲本组成的双列杂交试验,采用三倍体遗传模型分析蛋白质含量的遗传,经二年试验,结果表明:1.大麦蛋白质的 Wr/Vr 分析指出,F_2世代籽粒蛋白质含量符合加性-显性模型,不存在上位性效应。蛋白质含量高为隐性,Hiproly 具有最多的隐性基因;蛋白质含量低为显性,Ris(?)1508具有最多的显性基因。2.控制蛋白质含量的基因作用方式为超显性,且显性作用大于加性作用。但如用二倍体遗传模型分析则为部分显性,((?)/(?))^(1/2)=0.7503,因此,二种遗传模型的分析结果有较大的差异。3.根据大麦蛋白质含量的这种遗传特点,在以高蛋白质含量为育种目标时,可在杂种较高世代选择。反之,则可在较低世代选择。

Using the triploid genetic model,the genetic behavior of the grain protein content inbarley was studied with a 6×6 diallel set of crosses.The results of two years,studiesshowed that:1.The Wr/Vr regression analysis indicated that:the genetic behavior of the proteincontant of the F_2 grains was in accordance with additive-dominance model and there wasno epistasis.Genes conditioning high PC were recessive;Hiproly possessed more recessivehigh PC genes than the others.Genes conditioning low PC were dominant;Riso 1508 pos-sessed more dominant low PC genes than the others.2.The expression of genes conditioning PC was overdominance with the triploidgenetic model,and the effect of dominance was much greater than the additive effect.How-ever,if diploid genetic model were used,the genetic expression of these genes would havechanged into partial dominance.Therefore apparenthy different results would be obtainedby using different genetic models in the analysis.3.According to these genetic characteristics of barley concerning PC,if high PC is themain objective,selection for higher PC should be practiced in later generations,whereas se-lection for lower PC should be practiced in earlier generations if low PC is the mainobjective.