野生二粒小麦(Triticum dicoccoides)是小麦抗病育种的重要资源库之一。来自以色列Mount Hermon的野生二粒小麦材料IW3和IW10对我国小麦白粉病菌生理小种E09表现高抗。对硬粒小麦Langdon与IW3和IW10两个杂交组合F2分离群体和F3家系的遗传分析表明,IW3和IW10对小麦白粉菌E09的抗性均受显性单基因控制,暂被命名为MlIW3和MlIW10。采用BSA法和SSR标记分析,筛选到与抗白粉病基因MlIW3和MlIW10连锁的5个SSR标记,这两个基因均位于Xbarc84和Xwmc326之间,顺序为Xbarc84–4.6cM–MlIW3–1.6cM–Xwmc326和Xbarc84–6.6cM–MlIW10–0.6cM–Xwmc326。根据SSR分子标记的遗传图谱和在中国春的缺体-四体、双端体和缺失系的定位结果,这两个抗白粉病基因被定位在3BL染色体的末端。根据MlIW3和MlIW10的来源和分子标记定位结果,推断这两个基因可能是小麦抗白粉病基因Pm41或其等位基因或位于同一个基因簇中。
Powdery mildew, caused by Blumeria graminis f. sp. tritici (Bgt), is a major wheat disease in the world. Deployment of resistant varieties is considered the most economical and effective way for controlling the disease. Wild emmer is one of the important genetic resources for wheat disease resistance genes. Two wild emmer accessions, IW3 and IW10, collected from Mount Hermon, Israel, are highly resistant to prevailing Bgt isolate E09. Genetic analyses of the F2 populations and F3 progenies derived from the crosses between Triticum durum cultivar Langdon and IW3 or IW10 indicated that each accession possessed a single dominant gene, temporarily designated MUW3 and MUWIO, respectively, conferred resistance to Bgt isolate E09. Bulked segregant analysis (BSA) and SSR mapping revealed that both MIIW3 and MUWIO were flanked by SSR markers Xbarc84 and Xwmc326 with genetic distances of Xbarc84-4.6 cM-MIlW3-1.6 cM-Xwmc326 and Xbarc84-6.6 cM-MIIWIO-0.6 cM- Xwmc326. Both MIlW3 and MIlWIO were physically mapped on the distal bin of chromosome 3BL using Chinese Spring nulli- somic-tetrasomic, ditelisomic, and deletion lines. According to the collecting geographic sites of 1W3 and IW10 in Israel and the SSR mapping data, MIlW3 and MllWIO appear to be the same or allelic to wild emmer derived powdery mildew resistance gene Pm41 or in the same cluster with it.