陆地棉×瑟伯氏棉杂种后代主要经济性状的遗传分析

用G.hirsutum作母本,G.thurberi作父本进行种间杂交,经染色体加倍获得可育杂种.对杂种后代8个经济性状的遗传变异规律进行了分析,绒长、籽指的变异系数较小,遗传力较高,分别为62.39%和51.02%,早期世代即可进行单株选择,遗传力较低的其它性状,早期时代以混合选择为宜,单株选择在后期世代才有效.在开放授粉的条件下,除单纤维强度外,各有益性状值均随世代数的递增而有不同程度的增加,用陆地棉连续回交,各种经济性状在后代中恢复得更快.连续自交不利于各种有益特征特性的累积和加强.

Genetic Analysis of the Main Economic Characters of the Hybrid Progeny between G.hirsutum and G.thurberi

The fertile hybrids were produced by crossing the upland cotton used as female parent with the wild thurber cotton as male parent when chromosomes were doubled. The genetic variation were analysed on main economic characters in their hybrid progenies. The results indicated that the varia-tional coefficients of both fibre length and seed index were lower, and the hereditary capacities were higher, which were 62.39% and 51.02% respectively, so the plant selection could be conduct from early generation, but the variation coefficients of boll number per plant, seed cotton per boll, seeds per boll, ginning outturn, ginning index fibre tensity were larger, and their hereditary capacities were low, so that mixed selection are suited for early generations and the plant selection will be effective at later stage.Under open pollination condition the useful characters were increased to some extent at later generation except the fibre tensity. Back-cross with the upland cotton continuously the economic characters were restored more faster in the progenies but continuous self-cross is unfavoreable to tne accumulation and reinforcement of the profitable characters.