Wheat stripe rust is a devastating disease in many regions of the world. In wheat, 49 resistance genes for stripe rust have been officially documented, but only three genes are cloned, including the race-specific resistance YrlO candidate gene （YrlOca） and slow-rusting genes Lr34/Yr18 （hereafter designated as Yrl8） and Fr36. In this study, we developed gene-specific markers for these genes and used them to screen a collection of 659 wheat accessions, including 485 Chinese cultivars. Thirteen percent and eleven percent of the tested Chinese cultivars were positive for the markers for YrlOca and Yr18nn （the resistant haplotype of YrlS）, respectively, but none were positive for the Yr36 marker. Since there is a limited use of the YrlO gene in Chinese wheat, the relatively high frequency of wheat varieties with the YrlOcG marker suggests that the identity of the YrlO gene is unknown. With regards to the Yr18 gene, 29% of the tested cultivars that are used in the Middle and Lower Yangtze Valleys＇ winter wheat zone were positive for Yrl8RH markers. A non-functional allele of Yrl8Rn was identified in ＇Mingxian 169＇, a commonly used susceptible check for studying stripe rust. The data presented here will provide useful information for marker-assisted selection for wheat stripe rust resistance.
Cuiling YuanHui JiangHonggang WangKun LiHeng TangXianbin LiDaolin Fu
基因组靶向定位诱导损伤技术(Targeting Induced Local Lesions In Genomes,TILLING)是在化学诱变和PCR定向筛选基础上发展起来的检测点突变的反向遗传学研究方法,在多种重要农作物上都有应用。本研究使用化学诱变剂甲基磺酸乙酯(Ethyl methane sulfonate,EMS)处理大麦品种‘Tamalpais’,获得了2154个M2株系,同时开发了基于芹菜内切酶CEL I(celery juice extract)的酶切筛选体系。针对植物水杨酸抗病途径相关的两个重要基因EDR1和NPR1,检测到5个M2突变株系。序列分析表明,2个突变发生在内含子、1个NPR1基因的同义突变、2个EDR1基因的错义突变(His351Tyr和Pro556Ser)。本项研究为麦类作物反向遗传学研究奠定了基础。
