Department of Plant Pathology, University of Wisconsin-Madison, Madison, WI, U.S.A.
Valley Laboratory, Connecticut Agricultural Experiment Station, Windsor, CT, U.S.A.
Phytopathology. 2024 Nov;114(11):2394-2400. doi: 10.1094/PHYTO-03-24-0094-R. Epub 2024 Nov 21.
Dollar spot is a destructive foliar disease of amenity turfgrass caused by spp. fungi, mainly , on the Northern United States region's cool-season grass. Oxalic acid (OA) is an important pathogenicity factor in related fungal plant pathogens such as ; however, the role of OA in the pathogenic development of remains unclear due to its recalcitrance to genetic manipulation. To overcome these challenges, a CRISPR/Cas9-mediated homologous recombination approach was developed. Using this novel approach, the oxaloacetate acetylhydrolase () gene that is required for the biosynthesis of OA was deleted from a wild-type (WT) strain. Two independent knockout mutants, Δ and Δ, were generated and inoculated on potted creeping bentgrass along with a WT isolate and a genome sequenced isolate LWC-10. After 12 days, bentgrass inoculated with the mutants Δ and Δ exhibited 59.41% lower dollar spot severity compared with the WT and LWC-10 isolates. OA production and environmental acidification were significantly reduced in both mutants when compared with the WT and LWC-10. Surprisingly, stromal formation was also severely undermined in the mutants in vitro, suggesting a critical developmental role of OA independent of plant infection. These results demonstrate that OA plays a significant role in virulence and provide novel directions for future management of dollar spot. [Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY 4.0 International license.
币斑病是一种破坏性的观赏草坪叶部病害，由 spp. 真菌引起，主要发生在北美北部地区的冷季草坪上。草酸（OA）是相关真菌植物病原体（如 ）的一个重要致病性因素；然而，由于其遗传操作的顽固性，OA 在 的致病发展中的作用尚不清楚。为了克服这些挑战，开发了一种基于 CRISPR/Cas9 的同源重组方法。利用这种新方法，从 野生型（WT）菌株中敲除了草酸乙酰水解酶（）基因，该基因是 OA 生物合成所必需的。生成了两个独立的敲除突变体 Δ 和 Δ，并与 WT 分离株和基因组测序分离株 LWC-10 一起接种到盆栽匍匐翦股颖上。接种后 12 天，突变体 Δ 和 Δ 接种的匍匐翦股颖的币斑病严重度比 WT 和 LWC-10 分离株低 59.41%。与 WT 和 LWC-10 相比，两个突变体的 OA 产生和环境酸化均显著降低。令人惊讶的是，突变体在体外的基质形成也受到严重破坏，这表明 OA 在不依赖植物感染的情况下在发育中起着关键作用。这些结果表明 OA 在 毒力中起重要作用，并为未来的币斑病管理提供了新的方向。[公式：见正文]版权所有 © 2024 作者。这是一篇 CC BY 4.0 国际许可下的开放获取文章。
