矮败小麦群体连续选择早代的遗传分析

Genetic Analysis of Successive Selection in Early Generation in Dwarfingsterile Wheat Population

以单株产量为育种目标，采用含未选对照系统的二向选择方案，针对由不同亲本构建的“矮败”小麦群体ＤＮＳ３，就株高、穗粒数、千粒重、小穗密度四个主要性状各自进行了三轮选择．结果表明，小穗密度选密、株高选矮的效果最佳，三轮平均进展分别是６７２％、６０２％，且其选择响应第１轮最大；穗粒数、千粒重的选择效果不理想．利用矮败小麦连续选择可克服株高升高的趋势，选择使群体的平均数向量位置迁移、群体内植株的分布频率改变．四个选择性状向下选择的变异系数呈现增加趋势．

he basic population was established through multiparent crossing by usign dwarfsterile wheat, and three cycles of twoway selection on four characters was conducted to improve grain weight/plant. The data obtained were pooled together to make a populationwise analysis. The results showed that the responses of selection for increasing the density of ear and decreasing plant height were significant, 6.72% and 6.02% respectively, over the basic population per cycle, and the values of first selection were maximal. Using dwarfsterile wheat could decrease plant height during successive selection. Selection made the mean vector move to the expected target, and changed the distribution of plant in the populations. The realized herilabilities in two derections were uneaqueal. The variantion coefficients of four characters for decreasing their values were increasing. 