Downie Rowena C, Bouvet Laura, Furuki Eiko, Gosman Nick, Gardner Keith A, Mackay Ian J, Campos Mantello Camila, Mellers Greg, Phan Huyen T T, Rose Gemma A, Tan Kar-Chun, Oliver Richard P, Cockram James
Genetics and Breeding Department, National Institute of Agricultural Botany, Cambridge, United Kingdom.
Plant Sciences Department, University of Cambridge, Cambridge, United Kingdom.
Front Plant Sci. 2018 Jul 4;9:881. doi: 10.3389/fpls.2018.00881. eCollection 2018.
is a necrotrophic fungal pathogen of wheat ( L.), one of the world's most important crops. mediates host cell death using proteinaceous necrotrophic effectors, presumably liberating nutrients that allow the infection process to continue. The identification of pathogen effectors has allowed host genetic resistance mechanisms to be separated into their constituent parts. In , three proteinaceous effectors have been cloned: , , and . Here, we survey sensitivity to all three effectors in a panel of 480 European wheat varieties, and fine-map the wheat SnTox3 sensitivity locus using genome-wide association scans (GWAS) and an eight-founder wheat multi-parent advanced generation inter-cross (MAGIC) population. Using a Bonferroni corrected ≤ 0.05 significance threshold, GWAS identified 10 significant markers defining a single locus, , located on the short arm of chromosome 5B explaining 32% of the phenotypic variation [peak single nucleotide polymorphisms (SNPs), Excalibur_c47452_183 and GENE-3324_338, -log = 20.44]. Single marker analysis of SnTox3 sensitivity in the MAGIC population located via five significant SNPs, defining a 6.2-kb region that included the two peak SNPs identified in the association mapping panel. Accordingly, SNP Excalibur_c47452_183 was converted to the KASP genotyping system, and validated by screening a subset of 95 wheat varieties, providing a valuable resource for marker assisted breeding and for further genetic investigation. In addition, composite interval mapping in the MAGIC population identified six minor SnTox3 sensitivity quantitative trait loci, on chromosomes 2A (value = 9.17), 2B (, = 0.018), 3B (, = 48.51), 4D (, = 0.028), 6A ( = 8.51), and 7B (, = 0.020), each accounting for between 3.1 and 6.0 % of the phenotypic variance. Collectively, the outcomes of this study provides breeders with knowledge and resources regarding the sensitivity of European wheat germplasm to effectors, as well as simple diagnostic markers for determining allelic state at .
是小麦（L.）的一种坏死营养型真菌病原体，小麦是世界上最重要的作物之一。通过蛋白质类坏死营养效应子介导宿主细胞死亡，推测这些效应子释放出营养物质，使感染过程得以继续。病原体效应子的鉴定使得宿主遗传抗性机制能够被分解为其组成部分。在[研究对象]中，已克隆出三种蛋白质类效应子：[效应子名称1]、[效应子名称2]和[效应子名称3]。在此，我们检测了480个欧洲小麦品种对这三种效应子的敏感性，并使用全基因组关联扫描（GWAS）和一个由八个亲本组成的小麦多亲本高级世代杂交（MAGIC）群体对小麦SnTox3敏感性位点进行精细定位。使用经Bonferroni校正的P≤0.05显著性阈值，GWAS鉴定出10个显著标记，定义了一个位于5B染色体短臂上的单一基因座[基因座名称]，解释了32%的表型变异[峰值单核苷酸多态性（SNP），Excalibur_c47452_183和GENE - 3324_338，-logP = 20.44]。对MAGIC群体中SnTox3敏感性进行单标记分析，通过五个显著的SNP定位到[基因座名称]，定义了一个6.2kb的区域，该区域包含在关联作图群体中鉴定出的两个峰值SNP。因此，将SNP Excalibur_c47452_183转换为KASP基因分型系统，并通过对95个小麦品种的一个子集进行筛选进行了验证，为标记辅助育种和进一步的遗传研究提供了宝贵资源。此外，在MAGIC群体中进行复合区间作图，鉴定出六个较小的SnTox3敏感性数量性状基因座，分别位于2A（LOD值 = 9.17）、2B（[相关参数1]，P = 0.018）、3B（[相关参数2]，P = 48.51）、4D（[相关参数3]，P = 0.028）、6A（LOD = 8.51）和7B（[相关参数4]，P = 0.020）染色体上，每个基因座解释的表型变异在3.1%至6.0%之间。总体而言，本研究的结果为育种者提供了有关欧洲小麦种质对[效应子名称]效应子敏感性的知识和资源，以及用于确定[基因座名称]等位基因状态的简单诊断标记。
