短季棉常用亲本早熟性状的遗传及配合力研究

Study on Heredity and Combining Ability of Earliness of Short Season Cotton

采用9×9不完全双列杂交设计,分析了短季棉早熟及其相关性状的遗传特性、配合力和杂种优势表现,结果表明:短季棉的早熟性状由加性遗传效应和显性遗传效应共同作用,同时有不可忽视的加性、显性效应与环境的互作;全生育期、株高、衣分、铃重、霜前花率有较高的狭义遗传力,为0.262～0.528,特别是衣分和铃重受环境影响较小,可早代和异地选择;而果枝始节受环境条件影响较大;但在同一地区,果枝始节的狭义遗传力较高,为0.244～0.652,作为早熟性的选择指标是可靠的;在研究的9个材料中,有4个短季棉的早熟性的一般配合力较好,46个组合中有16个组合的早熟性及产量性状的特殊配合力均较好,其中以3个三个组合的产量及早熟性的综合性状较优,霜前皮棉较其优良亲本增产15%以上。

The 9×9 incomplete diallel crosses were designed between 7 short season , 1 middle mature and 1 late mature cotton varieties. The results showed that both dominant and additional effect played important roles in genetic characteristics for earliness and yield of short-season cotton, and the reaction between genetic effect and environment couldn't be neglected. These traits with high heredity, about 0.262～0.528, including growth and development stage, percentage of lint, boll weight, and percentage of cotton harvested before frost could be selected seriously in early generations. The percentage of lint and boll weight were affected no-significantly in different environment, in opposition to the first branch. But in a same place without environment effect, the heredity of the first branch was high, about 0.244～0.652. So growth and development stage, percentage of pre-frost and the first branch were certainty to estimate earliness of short season cotton in a same cotton ecology region. In addition, general combining ability (GCA) of 4 varieties in 9 experimental materials for earliness was higher than that of other varieties, 16 crosses with high specific combining ability(SCA) for early maturity and yield were found in the incomplete diallel crosses. The heterosis of CCRI 36×Liaomian9, Liaomian10 ×CCRI 27, CCRI 10×Yumian 1 was significant, and the increment over their parents was 15% at least for yield of cotton harvested before frost. Therefore, the research indicated that earliness and high yield crosses were selected easily from the hybridized combination between short season cotton with high GCA for earliness and middle mature varieties with high GCA for yield.