Genetic analysis of sugarcane mosaic virus resistance in the Wisconsin Diversity Panel of maize

Sugarcane mosaic virus (SCMV) and Maize dwarf mosaic virus can cause yield loss in maize (Zea mays L.). Previous studies identified two key genomic regions controlling host resistance: Scmv1 on chromosome 6 and Scmv2 on chromosome 3. In this study a diverse set of 578 inbreds adapted to a northern US Corn Belt environment, was inoculated at the three-leaf stage with SCMV and rated for presence of virus symptoms at 7, 10, 14, 21, 28, and 35 d after inoculation. Scmv1 was present in all resistant inbreds. A single-nucleotide polymorphism associated with SCMV resistance was found 5 Mb downstream of the putative location of Scmv1, and resistance at this downstream locus was correlated with a group of inbreds containing the presence allele of a 2.7-Mb presence–absence variation (PAV) in the region encompassing Scmv1. The Scmv2 region was associated with resistance 35 d after inoculation only among the inbreds containing the presence allele, including Scmv1. Several other loci unlinked to Scm...甘蔗花叶病毒（Sugarcane mosaic virus, SCMV）与玉米矮花叶病毒均可造成玉米（Zea mays L.）产量损失。既往研究已鉴定出两个调控寄主抗性的关键基因组区域：位于6号染色体的Scmv1与位于3号染色体的Scmv2。本研究以适应美国北部玉米带环境的578份多样化自交系为材料，于三叶期接种SCMV，并分别在接种后7、10、14、21、28及35天对病毒症状出现情况进行评级。所有抗性自交系均携带Scmv1位点。研究在Scmv1推定位点下游5 Mb处发现了一个与SCMV抗性相关的单核苷酸多态性（single-nucleotide polymorphism, SNP），且该下游位点的抗性与携带Scmv1区域内2.7 Mb存在-缺失变异（presence–absence variation, PAV）存在等位基因的一类自交系相关。Scmv2区域仅在携带包括Scmv1在内的存在等位基因的自交系中，与接种后35天的抗性相关。另有多个与Scmv（原文未完整给出）未连锁的位点。