College of Plant Protection, Nanjing Agricultural University, Nanjing, Jiangsu, China.
College of Plant Health and Medicine, Qingdao Agricultural University, Qingdao, Shandong, China.
Phytopathology. 2020 Apr;110(4):790-794. doi: 10.1094/PHYTO-11-19-0407-R. Epub 2020 Mar 3.
is a major pathogen of maize that causes ear rot and produces mycotoxins. Phenamacril is a novel cyanoacrylate fungicide that exhibits favorable activity against species. In this study, the phenamacril-resistant mutants of were obtained by ultraviolet mutagenesis. Single point mutations of S73L or E276K in the myosin-1 FvMyo1 were proven to be responsible for the high-level resistance of to phenamacril. Phenamacril had a significant impact on the localization of the wild-type FvMyo1 (FvMyo1-green fluorescent protein [GFP]), but not on the mutated FvMyo1 (FvMyo1-GFP and FvMyo1-GFP) at the hyphal tips. Molecular docking analysis suggested that mutation (S73L or E276K) in FvMyo1 altered the binding mode and decreased the binding affinity between phenamacril and myosin-1. There was no significant fitness penalty in mycelial growth, conidiation, and virulence of associated with resistance to phenamacril. The results will enhance our understanding of the resistance mechanism of to phenamacril and provide new reference data for the management of maize ear rot.
是一种导致玉米穗腐病并产生真菌毒素的重要病原体。苯霜灵是一种新型的丙烯酰吗啉类杀菌剂，对 表现出良好的活性。本研究通过紫外线诱变获得了对苯霜灵具有高抗性的 突变体。证明肌球蛋白-1（FvMyo1）中的 S73L 或 E276K 单点突变是导致 对苯霜灵产生高水平抗性的原因。苯霜灵对野生型 FvMyo1（FvMyo1-绿色荧光蛋白[GFP]）的定位有显著影响，但对突变型 FvMyo1（FvMyo1-GFP 和 FvMyo1-GFP）在菌丝顶端的定位没有影响。分子对接分析表明，FvMyo1 中的突变（S73L 或 E276K）改变了结合模式，降低了苯霜灵与肌球蛋白-1的结合亲和力。与对苯霜灵的抗性相关的菌丝生长、产孢和致病力没有明显的适应度代价。该结果将增强我们对 对苯霜灵抗性机制的理解，并为玉米穗腐病的防治提供新的参考数据。
