Xu Hongxing, Yao Guoqi, Xiong Li, Yang Lili, Jiang Yumei, Fu Bisheng, Zhao Wenfang, Zhang Zhengzhi, Zhang Caiqin, Ma Zhengqiang
The Applied Plant Genomics Lab, Crop Genomics and Bioinformatics Center and National Key Lab of Crop Genetics and Germplasm Enhancement, College of Agricultural Sciences, Nanjing Agricultural University, Nanjing 210095, Jiangsu, People's Republic of China.
Theor Appl Genet. 2008 Aug;117(4):471-7. doi: 10.1007/s00122-008-0791-6. Epub 2008 May 27.
Triticum monococcum accession TA2026 showed resistance to wheat powdery mildew. To identify the resistance gene and transfer it to common wheat, genetic analysis and molecular mapping were conducted using an F2 population and derived F3 families from the cross of TA2026xM389. The results indicated that TA2026 possessed a recessive powdery mildew resistance gene. This gene was mapped to the terminal portion of chromosome 5AmL and flanked by SSR marker loci Xcfd39 and Xgwm126. Eight RFLP markers previously mapped to the terminal chromosome 5AmL were converted into STS markers. Three loci, detected by MAG1491, MAG1493 and MAG1494, the STS markers derived from RFLP probes CDO1312, PSR164 and PSR1201, respectively, were linked to this resistance gene with Xmag1493 only 0.9 cM apart from it. In addition, the STS marker MAG2170 developed from the tentative consensus wheat cDNA encoding the Mlo-like protein identified a locus co-segregating with Xmag1493. This is the first recessive powdery mildew resistance gene identified on chromosome 5Am, and is temporarily designated pm2026. We have successfully transferred it to a tetraploid background, and this resistance stock will now be used as the bridge parent for its transfer to common wheat.
一粒小麦种质TA2026对小麦白粉病表现出抗性。为了鉴定该抗性基因并将其转移到普通小麦中，利用TA2026与M389杂交产生的F2群体及其衍生的F3家系进行了遗传分析和分子定位。结果表明，TA2026含有一个隐性白粉病抗性基因。该基因被定位到5AmL染色体的末端，侧翼为SSR标记位点Xcfd39和Xgwm126。先前定位到5AmL染色体末端的8个RFLP标记被转化为STS标记。分别由RFLP探针CDO1312、PSR164和PSR1201衍生的STS标记MAG1491、MAG1493和MAG1494检测到的3个位点与该抗性基因连锁，其中Xmag1493与该抗性基因的距离仅为0.9 cM。此外，从推测的小麦共有cDNA编码的类Mlo蛋白开发的STS标记MAG2170鉴定出一个与Xmag1493共分离的位点。这是在5Am染色体上鉴定出的第一个隐性白粉病抗性基因，暂时命名为pm2026。我们已成功地将其转移到四倍体背景中，该抗性材料现在将用作将其转移到普通小麦中的桥梁亲本。
