棉花优异纤维品质性状的双列杂交分析

利用5个具有不同纤维品质性状的品种(系)配制完全双列杂交组合20个，通过亲本和F1的2年随机区组试验，结果为除纤维整齐度受环境等因素影响较大，其余性状主要受遗传因素控制；在与环境的互作中，纤维强度和长度的互作效应小，麦克隆值的加性和母体效应及伸长率的显性效应与环境的互作较大，均达到了显著水平；遗传主效中，所有的研究性状不存在母体效应，以加性为主；强度与长度加性遗传率高，分别占77．6％和73．2％；麦克隆值的加性效应占45．2％，显性效应所占的比例在纤维性状中最高，为11．5％。纤维品质性状的群体平均优势仅麦克隆值的较高(3．2％)，达到了显著水平，其余性状的优势仅为-0．4％-0．7％。纤维品质性状的遗传结果与杂种优势一致。在杂种优势利用时，可以通过双亲平均值的高低来预测F1的纤维品质表现。纤维强度、长度和细度的加性遗传率高，这些性状均可以早代选择。

Diallel Analysis of Superior Fiber Quality Properties in Selected Upland Cottons

Twenty cross combinations were produced using a complete diallel-mating system with five varieties or lines that differed in fiber properties in Upland cotton to determine the inheritance and breeding merits of superior fiber properties.Evaluations of parents and F1's were conducted in two years.The results showed that fiber length uniformity was greatly affected by environmental factors,whereas the other fiber properties were mainly controlled by genetic factors.There were no significant interaction effect of environment with genotype for fiber strength or length,but there were significant environment interactions with additive and maternal affects for Micronaire,and with the dominance effects for elongation.There were no maternal effect,and additive effects predominated for the all fiber properties.Additive heritability was high for fiber strength and length,77.6% and 73.2% respectively; for Micronaire,it was 45.2%,while the dominance effect was 11.5%,which was the highest among fiber properties.Micronaire had significant heterosis over mid-parent based on population mean(3.2%),while the other fiber properties showed no heterosis.Therefore,the performance of fiber properties in F1's can be predicted from the average value of both parents.Since the additive heritability of strength,length,and fineness of fiber were high,these traits can be selected in early generations in breeding for high quality fiber properties.