利用普通小麦测序草图可从基因组范围内对小麦单条染色体上的某个区段进行分析。Pm43是作物遗传与分子改良山西省重点实验室在小麦2D染色体长臂上定位的一个抗白粉病基因。利用信息学方法分析Pm43所在物理图谱、遗传图谱和基因组图谱上的位置,可为其精细定位乃至候选基因的确定提供参考。试验采用Pm43两侧标记序列进行比对,将Pm43定位于染色体C-2DL3-0.49区间的79~99 c M内,所在基因组区段为2DL_9835990~2DL_9823315。利用目前已克隆小麦抗病基因的保守基序作为探针,从目标区段内检索出89条包含抗病基因类似物(Resistance gene analogues,RGA)序列的scaffold,其中,36条scaffold被诊断出含有SSR位点,之后针对SSR位点开发分子标记。利用携带有Pm43的普通小麦材料CH5025、感白粉病材料台长29以及CH5025×台长29的F2作图群体的抗感池DNA,对开发的SSR标记进行连锁性检测,共筛选出4个多态性标记,从而将目标区段进一步确定在标记PK_9908430和NBS_9908778之间。最后经聚类分析,筛选出与已克隆Pm基因同源性较高的1个PK序列和1个NBS序列,且在粗山羊草2D染色体和水稻第4染色体中均存在与这2个序列同源的RGA表达序列。 A common wheat sequencing map can be used to analyze a segment of a single chromosome of wheat genome-wide. Pm43 is a powdery mildew resistance gene located on the long arm of wheat 2D chromosome in Key Laboratory of Crop Genetics and Molecular Improvement, Shanxi Province. The use of informatics method to analyze the physical map, genetic map and genome map where Pm43 is located can provide reference for its fine mapping and determination of candidate genes. Pm43 was mapped on both sides of Pm43 marker sequence. Pm43 was mapped to 79-99 c M in chromosome C-2DL3-0.49 interval. The genomic region was 2DL_9835990 ~ 2DL_9823315. Using the conserved motifs of cloned wheat disease resistance genes as probes, 89 scaffolds containing resistance gene analogues (RGA) sequences were searched out from the target region, of which 36 scaffolds were identified Contain the SSR site before developing a molecular marker for the SSR site. In this study, the SSR markers were sequenced by using the common wheat material CH5025 carrying Pm43, the length 29 of susceptible powdery mildew and the F2 mapping population of CH5025 × Taiwan 29. Four SSR markers were screened out The morphological markers thus further define the target segment between the markers PK_9908430 and NBS_9908778. Finally, one PK sequence and one NBS sequence with high homology with the cloned Pm gene were screened out by cluster analysis, and both of the two sequences were identical in both the 2D chromosome of O. capitatum and the 4th chromosome of rice The source of the RGA expression sequence.