【摘要】 为更好地对小麦K-CMS保持系的遗传背景进行分析,筛选优良亲本,以进一步提高小麦杂交育种的效率。利用SRAP技术,对30份小麦K-CMS保持系的遗传背景进行研究,以SRAP标记在30个品种之间扩增的多态性位点数据,采用Nei和Li的方法,计算品种间的遗传距离;以2年田间试验得到的品种株高、穗长、小穗数、穗下节长、穗粒草重、穗粒数、穗粒重、旗叶长等表现型性状平均数经正态标准化后,采用欧氏距离计算品种间遗传距离,再比较分析。分析表明,82对SRAP引物揭示出多态性,多态率68.3%,获得208条多态性谱带,平均每对引物产生3.68条多态性谱带,表现出较高的多态性。基于分子标记的聚类分析结果与系谱分析结果基本一致。若以整个遗传距离的总平均数作尺度对聚类图的结果进行分类,大致可分为6类。Mantel检测表明,SRAP标记数据计算的遗传距离矩阵和表现型计算的遗传距离矩阵存在极显著的相关性0.8123(t=11.325>t0.01)。SRAP标记是检测品种间遗传差异的有效方法,可为小麦K-CMS保持系种质资源遗传差异的研究提供理论依据。研究还证实,一个骨干亲本与由其衍生出来的品种(系)之间的遗传差异一般较小。更多还原

【Abstract】 To analyze the genetic background of the maintainer line for K-type cytoplasmic male sterility(CMS) in wheat, screen the excellent parents for breeding, and improve hybrid breeding efficiency in wheat, thegenetic diversity of 30 maintainer lines for K-CMS germplasm resources of wheat were assessed using SRAPmarkers in this study. SRAP markers were used to amplify the polymorphic loci in the 30 lines, the geneticdistances between cultivars were calculated by using Nei and Li methods. In 2 years field experiment, theaverage of phenotypic traits about plant height, panicle length, spikelet number, spike length, spike grassweight, grain number and grain weight per spike, length of flag leaf and so on were carried out in normalstandard, using Euclidean distance to calculate the genetic distance among varieties, and comparative analysis was conducted. Analysis showed that 82 pairs of SRAP primers revealed polymorphism, the polymorphism ratewas 68.3%, 208 polymorphic bands were obtained, the average of each pair of primers produced 3.68 polymorphic bands, showed high polymorphism. The results of cluster analysis based on molecular markersand pedigree analysis results were consistent. Taking the total average genetic distance as the scale, the resultsof cluster graph could be divided into 6 categories. Mantel detection showed that there was a very significantcorrelation between the genetic distance matrix of SRAP marker data and the expression pattern of the geneticdistance matrix(r=0.8123, t=11.325>t0.01). SRAP marker is an effective method to detect the genetic differenceamong cultivars, which can provide theoretical basis for the research of genetic difference of germplasmresources of K-CMS in wheat. Studies also confirm that the genetic difference between a backbone parent andthe breed derived from it is generally small.更多还原