Hou Yi-Hsuan, Zhang Ting-Xiang, Chen Ying-Lien
Department of Plant Pathology and Microbiology, National Taiwan University, Taipei, Taiwan.
Institute of Biotechnology, National Taiwan University, Taipei, Taiwan.
Front Plant Sci. 2025 Apr 14;16:1366158. doi: 10.3389/fpls.2025.1366158. eCollection 2025.
Bakanae, or foolish seedling disease of rice, is caused by the ascomycetous fungus , which is prevalent in many rice-growing countries. Current protection strategies depend on fungicides, but this results in chemical-resistant and detrimental environmental effects. It is known that calcineurin controls Ca signaling, which mediates growth, stress responses, and pathogenicity in fungi. Based on the pharmacological inhibition of calcineurin in , we discovered that calcineurin inhibitor FK506 or cyclosporin A can intensely prevent the growth of , and further investigated the feasibility of silencing calcineurin genes of in rice using host-induced gene silencing (HIGS) to confer resistance to bakanae disease. The constructs and were introduced into rice plants by using -mediated gene transformation, and the copy numbers of transgenes were examined by Southern blot hybridization in the transgenic lines. The results of pathogen inoculation assay and fungal biomass quantification demonstrated that the transgenic rice plants that carry the or construct had increased resistance against bakanae disease. We propose that RNAi-derived siRNAs might efficiently suppress the expression of calcineurin genes in , leading to impaired growth and poor colonization of in rice. These findings indicate that HIGS might be a potential disease management strategy for rice bakanae disease.
水稻恶苗病，又称水稻徒长病，由子囊菌引起，在许多水稻种植国家普遍存在。目前的防治策略依赖于杀菌剂，但这会导致抗药性并产生有害的环境影响。已知钙调神经磷酸酶控制钙信号传导，而钙信号传导介导真菌的生长、应激反应和致病性。基于对钙调神经磷酸酶的药理学抑制作用，我们发现钙调神经磷酸酶抑制剂FK506或环孢菌素A可以强烈抑制病菌的生长，并进一步研究了利用寄主诱导的基因沉默（HIGS）沉默水稻中病菌钙调神经磷酸酶基因以赋予对恶苗病抗性的可行性。通过农杆菌介导的基因转化将构建体导入水稻植株，并通过Southern杂交检测转基因系中转基因的拷贝数。病原菌接种试验和真菌生物量定量结果表明，携带构建体的转基因水稻植株对恶苗病的抗性增强。我们推测，RNA干扰产生的小干扰RNA可能有效抑制病菌中钙调神经磷酸酶基因的表达，导致病菌在水稻中的生长受损和定殖能力下降。这些发现表明，寄主诱导的基因沉默可能是水稻恶苗病潜在的病害管理策略。
