转基因抗虫棉纤维品质性状的遗传分析

 根据ADAA遗传模型分析了7个转基因抗虫棉亲本、两个非转基因抗虫亲本和36个半双列杂交F1的纤维品质性状的两年资料,估算各项遗传方差和成对性状间的遗传相关性。结果表明,转基因抗虫棉纤维品质的5个性状受加性、显性和上位性的共同控制,其中麦克隆值、2.5%纤维长度和纤维比强度以基因显性效应为主,麦克隆值和纤维整齐度以上位性效应为主。除纤维比强度外,其余4个纤维品质性状都受到环境互作效应的影响,且影响较大。遗传相关分析表明,纤维比强度与2.5%纤维长度的基因型相关和表型值相关达极显著水平,其中加性相关未达显著水平,显性相关达极显著水平。比强度与麦克隆值的基因加性相关也达极显著水平,但表型相关未达显著水平。利用亲本和F₁的资料预测了F₂的基因型值和杂种优势。结果表明,F₂代的麦克隆值、伸长率、2.5%纤维长度、整齐度、纤维比强度的中亲优势分别为1.0%, 8.5%, 0.8%, 0和2.9%, 无超亲优势。

Analysis of Genetic Effects for Fiber Quality in Transgenic Insect Resistant Cotton(G.hirsutum L.)

Nine parents which seven of them were transgenic insect resistant cotton cultivars with Bt developed in China and USA, and their 36 F₁ combinations were analyzed for five traits of fiber quality in two years by a genetic model of additive-dominance with interaction effects, and genetic variance components and correlations were estimated as well. The results showed that the five characters related fiber quality were controlled by additive effects, dominant effects and additive × additive effects. The main effects in micronaire, 2.5% staple strength were dominant effects, while elongation and uniformity were additive × additive effects. There were some interaction effects with large values between genotypes and environments for all five fiber traits except for fiber strength. The genotype and phenotype correlation coefficient between fiber strength and 2.5% staple length were significant, in which the dominant correlation were high, but there were no additive correlation between them. In the meanwhile, the additive genotype correlation between fiber strength and micronaire were significant, and their phenotype correlation was undetected. The F₂ genotypic value and their heterosis were analyzed and forecasted from the data of parents and their F₁. The result indicated that the heterosis in F₂ over mid-parent were 1.0%, -8.5%,-0.8%, 0,-2.9% in average for micronaire, elongation, 2.5% staple length, uniformity and fiber strength, respectively. There was no heterosis over the better parent.