陆海种间杂交纤维品质性状的遗传及其F1群体优势分析

Heterosis and Genetic Analysis of Fiber Quality Traits of Interspecific Hybrid of G. hirsutum L.× G.barbadense L.

以4个陆地棉品种(系)和3个海岛棉品种为亲本配制不完全双列杂交组合12个,采用包括基因型×环境互作的加性-显性(AD)遗传模型,通过对亲本和F1的2年随机区组试验数据分析,结果为:纤维整齐度受环境的影响较大,纤维长度、强度、麦克隆值及伸长率受环境的影响较小,纤维品质性状的遗传主要受遗传因素控制;所有的性状都存在显著或极显著的显性效应;麦克隆值只受显性效应控制,其它4个性状还存在极显著的加性效应;强度以加性效应为主,长度、整齐度和伸长率的显性效应值分别大于相应的加性效应值;所有性状的加性效应和显性效应与环境之间的互作效应都很小。长度、强度、麦克隆值和伸长率的广义遗传率都非常高,整齐度的广义遗传率较小。这些结果表明,除纤维强度外陆海杂种纤维品质性状的遗传中显性遗传效应明显,与陆陆杂种及海海杂种以加性遗传效应为主的结果不同。长度、强度、整齐度和伸长率具有明显的正向群体平均优势;麦克隆值有显著的负向群体平均优势和群体超亲优势。通过陆海杂交利用海岛棉的优质纤维性状时,强度宜早代选择,而其它性状的选择不宜太早。

12 F1, which combinations crossed with four G. hirsutum L. varieties （lines） and three G. Barbadense L. varieties according to incomplete diallel crossing design, were used to evaluate the heterosis and gene action of fiber quality traits of interspecific hybrid of G. hirsutum L. ×G. barbadense L. in 2003 and 2004, by the genetic model of additive-dominance and their interactions with environments by MINQUE（1） approaches. The results indicated that there existed significant or extremely significant dominant effect for all main fiber traits, and extremely significant additive effect for the other four traits except micronaire, and small interactions with the environmental factors for all fiber traits. Micronaire was only controlled by dominant effect. Strength was controlled mainly by additive effect, the dominant effect was comparatively smaller. Length, uniformity and elongation were controlled by additive effects and dominant effects together, their dominant effects were higher than their corresponding additive efffects. The broad inheritance of uniformity was low and that of the other four fiber traits were very high. The results showed that dominant effect was more evident for fiber traits, except strength, of interspecific hybrid of G. hirsutum L. × G. barbadense L. than that in intraspecific hybrid of G. hirsutum L. ×G. hirsutum L. ,or that in intraspecific hybrid of G. barbadense L. × G. barbadense L.. The population mean heterosis of length, strength, uniformity and elongation expressed significant positive value. The population mean heterosis and the better-parental heterosis of micronaire expressed significant negative value. Strength should be selected in early generations and other traits should be selected in middle or late generations, when good fiber quality traits of G. barbadense L. was utilized by interspecific crossing.