The emerging resistance of crop pathogens to fungicides poses a challenge to food security and compels discovery of new antifungal compounds. Here, we show that mono-alkyl lipophilic cations (MALCs) inhibit oxidative phosphorylation by affecting NADH oxidation in the plant pathogens Zymoseptoria tritici, Ustilago maydis and Magnaporthe oryzae. One of these MALCs, consisting of a dimethylsulfonium moiety and a long alkyl chain (C₁₈-SMe₂⁺), also induces production of reactive oxygen species at the level of respiratory complex I, thus triggering fungal apoptosis. In addition, C₁₈-SMe₂⁺ activates innate plant defense. This multiple activity effectively protects cereals against Septoria tritici blotch and rice blast disease. C₁₈-SMe₂⁺ has low toxicity in Daphnia magna, and is not mutagenic or phytotoxic. Thus, MALCs hold potential as effective and non-toxic crop fungicides.

作物病原体对杀菌剂的抗药性对食品安全提出了挑战，并迫使人们发现新的抗真菌化合物。在这里，我们显示单烷基亲脂性阳离子（MALCs）通过影响植物病原体Zymoseptoria tritici，Ustilago maydis和Magnaporthe oryzae中的NADH氧化来抑制氧化磷酸化。这些MALC之一由二甲基chain部分和长烷基链（C ₁₈ -SMe ₂ ⁺）组成，还诱导呼吸复合物I产生活性氧，从而触发真菌凋亡。此外，C ₁₈ -SMe ₂ ⁺激活先天植物防御。这种多重活性可有效保护谷物免受小麦黑斑病和稻瘟病的侵害。C ₁₈ -SMe ₂ ⁺对大型蚤（Daphnia magna）具有低毒性，并且没有致突变性或植物毒性。因此，MALC具有作为有效且无毒的农作物杀菌剂的潜力。