小麦种质N9134抗白粉病基因的SSR标记和染色体初步定位

普通小麦种质N9134含有野生二粒小麦AS846的抗白粉病基因，该种质对陕西省关中地区白粉病流行小种关中四号表现高抗。用高感小麦白粉病的普通小麦品种陕160和陕优225与N9134杂交，F1代对白粉病表现高抗，F2代抗病和感病植株的比例符合3∶1, 表明N9134苗期白粉病抗性由1对完全显性基因控制，暂定名为PmAS846。采用66个小麦SSR

SSR Markers and Preliminary Chromosomal Location of a Powdery Mildew Resistance Gene in Common Wheat Germplasm N9134

A powdery mildew resistance gene, originating from wild emmer (Triticum dicoccoides Thell.) accession ‘AS846’, was transferred to a common wheat line N9134. N9134 was highly resistant to the prevailing Erysiphe graminis f. sp. tritici Race Guanzhong No.4 in Shaanxi Province. F₁ plants of the crosses susceptible cultivars (Shaan 160 and Shaanyou 225)×N9134 were highly resistant to the powdery mildew race and the ratio of resistant and susceptible plants in F₂ progeny fitted the expected 3 to 1. The results indicated that powdery mildew resistance of N9134 at seedling stage was controlled by a single dominant gene. The gene is temporarily designated PmAS846. 92 and 84 F₂ plants of the crosses Shaan 160×N9134 and Shaanyou 225×N9134 were used for SSR analysis, respectively. 3 of 66 wheat microsatellite primer pairs WMS67, WMS213 and WMS37 generated polymorphic DNA fragments between the resistant and susceptible plants DNA pools. By analyzing the polymorphic markers in these segregating populations, the microsatellite locus Xgwm67 located on chromosome 5BL was found to be linked to the resistance gene PmAS846 with the estimated genetic distance of 20.6 cM, suggesting this gene might be located on the long arm of chromosome 5B.