Fusarium graminearum is one of the most frequent causal agents of the Fusarium Head Blight, a cereal disease spread throughout the world, reducing grain production and quality. F. graminearum isolates are genetically and phenotypically highly diverse. Notably, remarkable variations of aggressiveness between isolates have been observed, which could reflect an adaptive potential of this pathogen. In this study, we aimed to characterize the genetic basis of aggressiveness variation observed in an F1 population (n = 94), for which genome sequences of both parental strains are available. Aggressiveness was assessed by a panel of in planta and in vitro proxies during two phenotyping trials including, among others, disease severity and mycotoxin accumulation in wheat spike. One major and single QTL was mapped for all the traits measured, on chromosome I, that explained up to 90% of the variance for disease severity. The confidence interval at the QTL spanned 1.2 Mb and contained 428 genes on the reference genome. Of these, four candidates were selected based on the postulate that a non-synonymous mutation affecting protein function may be responsible for phenotypic differences. Finally, a new mutation was identified and functionally validated in the gene FgVe1, coding for a velvet protein known to be involved in pathogenicity and secondary metabolism production in several fungi.

Fusarium graminearum是镰刀菌枯萎病（Fusarium Head Blight）最常见的病原体之一，枯萎病是一种在世界范围内传播的谷物病害，会降低粮食产量和质量。F. graminearum分离株在遗传和表型上高度多样化。值得注意的是，已经观察到分离株之间侵袭性的显着变化，这可能反映了这种病原体的适应性潜力。在这项研究中，我们旨在表征在 F1 种群（n = 94）中观察到的侵略性变异的遗传基础，这两种亲本菌株的基因组序列都可用。侵略性由一组在足底和体外评估两项表型试验期间的代理，其中包括疾病严重程度和小麦穗中真菌毒素的积累。在染色体 I 上为所有测量的性状绘制了一个主要和单一的 QTL，这解释了高达 90% 的疾病严重程度的方差。QTL 的置信区间跨越 1.2 Mb，包含参考基因组上的 428 个基因。其中，基于影响蛋白质功能的非同义突变可能导致表型差异的假设，选择了四个候选者。最后，在FgVe1基因中发现了一个新的突变并在功能上得到了验证，该突变编码了一种已知与几种真菌的致病性和次级代谢产生有关的天鹅绒蛋白。