“矮败”小麦回交群体若干重要性状的相关分析

用矮败小麦不育株为母体，40个普通小麦品种（系）为父本连续回交三次，共衍生出120份后代群体，通过对各群体的不育株，可育株的株高，穗长，千粒重等性状的相关分析，探讨了“矮败”基因回交转育的效应。不育株：连续注入父本遗传种质，对其各性状素现影响较小。其株高一般45cm左右，回交几代后，高秆父本衍生的后代略高于中矮秆父本的后代。与可育株相比，其穗子较长，小穗数多，但千粒重较低，开花一般迟2－14d，而早花父本衍生的后代花期也早，迟花父本后代花期较迟。可育株：性状表现与父本关系密切，并随回交世代的增加而逐渐接近父本，其F1，BC1F1，BC2F1各世代群体株高依父本株高的直线回归方程分别为：YF1＝56.210 0.3194X,YBC1F1=40.435 0.5119X,YBC2F1=21.F687 0.7759X.大穗多花多粒的父本衍生的可育株一般也是大穗多花多粒，千粒重大都表现超父优势，早花父本衍生的可育株花期早于迟花父本后代。

Analysis of Some Characters of Different Generation Transferred by Backcrossing to the Dwarfing-Sterile Wheat

This paper discussed the effect of transferring dwarfing sterile gene by backcrossing. By means of 3 continuous generations, 120 colony were derived from the dwarfing sterile wheat backcrossed with 40 varieties ( T. aestivum ). The sterility was less affected by continuous backcrossed with male parents. Its height was around 45 cm. Compared with fertility, the sterility showed longer spike, more spikelet, lower kernel weight and 2~4 days later flowering related to the male backcross parents. To the fertility, it was closly related to the male backcross parents, and got closer and closer to that of male parent in generation and generation. The regression equations of fertility height (Y) in F 1?BC 1F 1?BC 2F 1 according to male parent height (X) were as follows: Y F1 =56.210+0.3194X, Y BC1F1 =40.435+0.5119X, Y BC2F1 =21.687+0.7759X.