Department of Agronomy, Kansas State University, Manhattan, KS, USA.
Phytopathology. 2011 Nov;101(11):1322-9. doi: 10.1094/PHYTO-02-11-0041.
Soilborne wheat mosaic virus (SBWMV) is one of the most important winter wheat pathogens worldwide. To identify genes for resistance to the virus in U.S. winter wheat, association study was conducted using a selected panel of 205 elite experimental lines and cultivars from U.S. hard and soft winter wheat breeding programs. Virus symptoms were evaluated twice in virus-infected fields for the panel at Manhattan, KS in spring 2010 and 2011 and for a subpanel of 137 hard winter wheat accessions at Stillwater, OK in spring 2008. At the two locations, 69.8 and 79.5% of cultivars were resistant or moderately resistant to the disease, respectively. After 282 simple-sequence repeat markers covering all wheat chromosome arms were scanned for association in the panel, marker Xgwm469 on the long arm of chromosome 5D (5DL) showed a significant association with the disease rating. Three alleles (Xgwm469-165bp, -167bp, and -169bp) were associated with resistance and the null allele was associated with susceptibility. Correlations between the marker and the disease rating were highly significant (0.80 in Manhattan at P < 0.0001 and 0.63 in Stillwater at P < 0.0001). The alleles Xgwm469-165bp and Xgwm469-169bp were present mainly in the hard winter wheat group, whereas allele Xgwm469-167bp was predominant in the soft winter wheat. The 169 bp allele can be traced back to 'Newton', and the 165 bp allele to Aegilops tauschii. In addition, a novel locus on the short arm of chromosome 4D (4DS) was also identified to associate with the disease rating. Marker Xgwm469-5DL is closely linked to SBWMV resistance and highly polymorphic across the winter wheat accessions sampled in the study and, thus, should be useful in marker-assisted selection in U.S. winter wheat.
土壤传播小麦花叶病毒（SBWMV）是世界上最重要的冬小麦病原体之一。为了鉴定美国冬小麦中抗该病毒的基因，对美国硬粒和软粒冬小麦育种种质资源中的 205 个精选实验品系和品种进行了关联研究。2010 年和 2011 年，在堪萨斯州曼哈顿的病毒感染田间，对该品系进行了两次病毒症状评估；2008 年，在俄克拉荷马州斯蒂尔沃特的一个 137 个硬粒冬小麦品系亚系中进行了两次评估。在这两个地点，分别有 69.8%和 79.5%的品种对该病害表现为抗性或中度抗性。在对该品系的 282 个覆盖所有小麦染色体臂的简单序列重复标记进行了关联扫描后，5D 染色体长臂上的标记 Xgwm469（5DL）与疾病评级显著相关。三个等位基因（Xgwm469-165bp、-167bp 和-169bp）与抗性相关，而无效等位基因与易感性相关。标记与疾病评级之间的相关性高度显著（曼哈顿为 0.80，P < 0.0001；斯蒂尔沃特为 0.63，P < 0.0001）。等位基因 Xgwm469-165bp 和 Xgwm469-169bp 主要存在于硬粒冬小麦群体中，而等位基因 Xgwm469-167bp 则在软粒冬小麦中占优势。169 bp 等位基因可以追溯到“牛顿”，而 165 bp 等位基因可以追溯到节节麦。此外，还在 4D 染色体短臂（4DS）上鉴定到一个与疾病评级相关的新位点。标记 Xgwm469-5DL 与 SBWMV 抗性紧密连锁，在研究中采样的冬小麦品种中高度多态性，因此应该对美国冬小麦的标记辅助选择有用。
