Abstract Although better known as a pathogen of wheat stem bases, Fusarium pseudograminearum also causes Fusarium head blight. A natural isolate of F. pseudograminearum was identified that showed severely reduced virulence towards wheat heads and a map-based cloning approach was undertaken to identify the genetic basis of this phenotype. Using a population of 95 individuals, a single locus on chromosome 1 was shown to be responsible for the low virulence. Fine mapping narrowed the region to just five possible SNPs of which one was in the F. pseudograminearum homologue of velvet A. Knockout mutants of velvet A, which were non-pathogenic towards wheat, confirmed that velvet A regulates virulence in this pathogen. The mutation in velvet A was only found in a single field isolate and the origin of the mutation is unknown.

中文翻译：

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基于图谱的克隆确定天鹅绒 A 是小麦头感染期间假禾本科镰刀菌毒力的关键组成部分

摘要 虽然作为小麦茎基部的病原体而广为人知，Fusarium pseudograminearum 也会引起镰刀菌赤霉病。鉴定出一种假禾本科假单胞菌的天然分离物，其对小麦头部的毒力严重降低，并采用基于图谱的克隆方法来鉴定该表型的遗传基础。使用 95 个人的群体，显示 1 号染色体上的单个基因座是造成低毒力的原因。精细定位将该区域缩小到仅五个可能的 SNP，其中一个位于天鹅绒 A 的 F.pseudograminearum 同源物中。 天鹅绒 A 的敲除突变体对小麦无致病性，证实了天鹅绒 A 调节该病原体的毒力。天鹅绒 A 的突变仅在单一的野外分离物中发现，突变的来源未知。