水稻倒伏指数的配合力分析

采用抗倒伏能力不同的遗传类型的粳稻品种，按Ｇｒｉｆｉｎｇ方法Ⅰ配制成５×５完全双列杂交Ｆ１、Ｆ２，以倒伏指数作为衡量抗倒伏能力的指标。结果表明，倒伏指数的遗传以加性效应为主，倒伏指数的一般配合力在早期世代间较稳定，特殊配合力变化较大、倒伏指数的一般配合力可以在早期世代测定，水稻倒伏指数的一般配合力效应值（ｇｉ）与亲本倒伏指数呈正相关，从亲子间倒伏指数关系的分析中也得出，双亲倒伏指数的平均值对后代倒伏指数的影响大于亲本之一的影响。因此，在抗倒伏育种中最好采用倒伏指数低×低的组配方式。

COMBINING ABILITY ANALYSIS OF LODGING IN RICE

Lodging index (LI) was used as the criteria for evaluating the ability of resistant to lodging, and F 1 , F 2 populations were established from 5 parental cultivars which were different genetically in resistance to lodging, based on Griffing Method I in which the complete parallel crosses of 5×5 were performed. The result showed that the inheritance of LI was mainly controlled by additive action, and in early generations general combining ability (GCA) of LI was stable, but the special combining ability (SCA) varied greatly. The GCA effect of LI may be evaluated in early generations. The correlation between GCA effects (g i ) of LI and the LI of parents was positive. The result of LI analysis between parents and their progenies indicated that the means of parental LI have stronger effects on the progenies than any parent involved. Therefor, in breeding project for resistance to lodging, it isbest to select the crosses composed of low LI parents.