亲本类型对提型恢复系自身育性及其恢复度的影响

Effects of Parentage on the Fertility and Sterility Restoring Ability of Restorer Lines with Triticum Timopheevi Cytoplasm

通过对不同世代提型恢复系自身结实率的连续考察,发现经过 F_2代的严格选择后,多数 F_3恢复系的自身结实率超过了80%;但同一株系后代的不同个体之间有一定的差异。这种差异可以一直保持到 F_7代。F_5群体的自身结实率与其恢复度呈显著正相关,r=0.879。亲本类型只影响恢复基因在后代群体中的纯合速度,与高代恢复系(F_5代以上)的结实率和恢复度无明显相关。自身结实率高且群体中变异系数小的恢复系对所有的不育系都能高度恢复;而结实率高但变异系数大的恢复系其恢复度会因不育系的不同而变化。主效恢复基因未完全纯合可能是高代恢复系的恢复度在不同不育系上出现分离的主要原因。对根据自身结实率及其变异系数进行恢复系选育的效率进行了讨论。

Seed set ratio of restorer lines(R-lines)with T.timopheevi cytoplasm was investigated for 3 years.Experimental results showed that after strict selection at the F_2 generation,the seed set ratio of most F_3 lines exceeded 80%;but there was apparent variance among the population descended from the same F_2 plant.This variance could be found even at the F_7 for some crosses.Fertility of F_5 lines was significantly and poistively related to their sterility restoring ability,r=0.879,Parentage only imposed its effect on the ho- mozygous speed of Rf genes but not on restoring ability of these R-lines at F_5 or more.R-lines with a high fertility and little variance in it displayed a high restoring ability for all A-lines.Otherwise,the restoring a- bility of R-lines with a high fertility and big variance in it changed with A-lines.It is suggested that the variance of restoring ability among A-lines was mainly caused by the heterozygosity of major Rf genes in the R-line.The efficiency of using seed set ratio and its variance among population to select R-lines are dis- cussed.