回交对栽培大豆×半野生大豆杂交后代的改良效果

以３个随机交配的栽培大豆×半野生大豆杂交组合的Ｆ１代做待改良群体，分别用有限性、亚有限性、无限性等３个不同结荚习性大豆品种做回交亲本，组配９个回交组合。通过对这９个组合回交一代（ＢＦ１）和３个自交Ｆ２代株高、主茎粗、有效分枝数、百粒重及蛋白质含量的分析比较可以看出：以有限性品种做回交亲本对种间杂种后代降低株高、增加茎粗效果最佳，亚有限品种次之，无限品种效果最差。对分枝这一性状的改良应选用独秆型品种进行回交，而和品种本身的结荚习性无关。百粒重大的回交亲本对克服种间杂交后代的小粒性效果最佳。只要亲本选配得当，回交Ｆ１代即可分离出百粒重接近栽培大豆的单株。在蛋白质含量上用高蛋白品种进行连续回交，可逐年提高杂种后代的蛋白质含量。选用进化程度较高的半野生大豆做亲本，其组合的自交Ｆ２代及ＢＦ１代即可获得一定数量的、可供选择的单株

The Improvement Effect of Backcross to Cross Progenies between Cultivated Soybean (G. max) and Semi Wild Soybean(G.gracilis)

The F 1 (to be improved population) from three random crosses between cultivated soybean (G.max) and semi wild soybean (G.gracilis) of such crosses were backcrossed with different growth types of G.max (det, semi det, indet) which were taken as recurrent parents and 9 backcrossed combinations were comparatived. The results showed that definite types of soybean were more effective to reduce plant height of hybird progenies and add it's main diamater than semi det than indet when they were used as recurrent parents. The improvement effect of actual branch were more effective with single stem soybean varieties to backcrossing recurrents of big 100 seed weight were most effective for overcoming the small grain charaters of hybrid progenies. Continuous backcrossed were more effective with high protein soybean varieties in raising the protein contents of the hybrid progenies year by year.