小麦F4代株系的DNA位点纯合率和农艺性状变异幅度

The Homozygous DNA Locus Ratio and the Variation Range of Agronomic Traits of Wheat F_4 Lines

近年来,我国部分育种者为了加快小麦育种速度而缩短系统选择年限,用F4代株系进行品种比较试验,并将其作为品种参加区域试验。本研究以10个小麦杂交组合F4代株系及其亲本为试验材料,对不同株系及其亲本的DNA位点纯合率和重要农艺性状的稳定性进行研究。结果表明,10个F4代株系的DNA位点纯合率在83.0%～94.8%之间,其亲本的DNA位点纯合率均高于95%。以DNA位点纯合率≥95%的品种为对照,10个F4代株系中仅BF-2003-82-17的农艺性状变异幅度在对照品种的变异范围之内,其DNA位点纯合率为94.2%,接近95%。其余9个F4代株系均有变异幅度大于对照品种或仍在分离的农艺性状,初步证明大多数F4代株系的一致性和稳定性尚不符合要求,只有极少数株系具备了一致性和稳定性。

In order to shorten breeding time, some wheat breeders used F4 lines as cultivars to carry out comparison tests and submit them to wheat cultivar regional tests. In this study, ten of F4 lines and their parents were employed to detect the homozygous DNA locus ratio and the uniformity as well as the stability of main agronomic traits. The results showed that the homozygous DNA locus ratios often ofF4 lines were 83.0%-94.8%. The ratios of their parents were higher than 95%. The variation range of agronomic traits of F4 line BF-2003-82-17 was within the scope of the control cultivars by comparing with the control cultivars which the homozygous DNA locus ratio was higher than 95%. The homozygous DNA locus ratio of BF2003-82-17 was 94.2% , which was closed to 95%. Some agronomic traits of the other nine lines presented higher variation coefficient than that of the control cultivars, and some agronomic traits were still separating. It preliminary proves that the uniformity and stability of the most ofF4 lines do not accord with the requirements yet. Only a few lines possess the uniformity and stability.