Zhang Meihui, Zhou Meijiao, Jia Yunmeng, Li Xipeng, Wang Aolin, Liu Taiguo, Zhou Yilin, Liu Wei, Fan Jieru
State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China.
College of Plant Protection, Shenyang Agricultural University, Shenyang, China.
Front Plant Sci. 2025 Jun 25;16:1628068. doi: 10.3389/fpls.2025.1628068. eCollection 2025.
f. sp. (), the causal agent of wheat powdery mildew, poses a significant threat to global wheat production. As an obligate biotroph, is recalcitrant to stable genetic manipulation. Although host-induced gene silencing has been used for gene function studies, it remains ineffective for targeting genes active during pre-penetration stages. Consequently, the functional roles of many genes during pre-penetration stages remain largely unexplored. In this study, the feasibility of spray-induced gene silencing (SIGS) to characterize gene function during pre-penetration stages was evaluated. The results demonstrated that conidia and germ tubes efficiently took up environmental double-stranded RNA (dsRNA), enabling the targeted silencing of . Exogenous application of effectively reduced target gene expression and impaired infection of . silencing predominantly induced abnormal appressoria and reduced disease severity when dsRNA was applied at 6 and 10 hours post-inoculation (hpi). In contrast, was almost not silenced when dsRNA was applied at 2 hpi. These findings established SIGS as a promising tool for gene functional studies during the pre-penetration stages of and highlight the potential of RNA-based strategies for the control of wheat powdery mildew.
小麦白粉病菌（Blumeria graminis f. sp. tritici）是小麦白粉病的致病因子，对全球小麦生产构成重大威胁。作为一种专性活体营养型病原菌，它难以进行稳定的遗传操作。尽管宿主诱导的基因沉默已用于基因功能研究，但对于靶向在穿透前阶段活跃的基因仍然无效。因此，许多小麦白粉病菌基因在穿透前阶段的功能作用在很大程度上仍未得到探索。在本研究中，评估了喷雾诱导基因沉默（SIGS）在表征穿透前阶段基因功能方面的可行性。结果表明，小麦白粉病菌分生孢子和芽管能有效摄取环境双链RNA（dsRNA），从而实现对小麦白粉病菌的靶向沉默。外源施用dsRNA有效降低了靶基因表达并削弱了小麦白粉病菌的侵染。当在接种后6小时和10小时（hpi）施用dsRNA时，小麦白粉病菌沉默主要诱导了异常附着胞的形成并降低了病害严重程度。相比之下，在接种后2小时施用dsRNA时，小麦白粉病菌几乎未被沉默。这些发现确立了SIGS作为在小麦白粉病菌穿透前阶段进行基因功能研究的一种有前景的工具，并突出了基于RNA的策略在控制小麦白粉病方面的潜力。
