Antifungal Activity and Biochemical Mechanisms of Artemisinin Against the Phytopathogen Sclerotinia sclerotiorum

Sclerotinia sclerotiorum (Lib.) de Bary is a globally distributed necrotrophic Fungal pathogen capable of infecting a wide range of crops. While conventional chemical fungicides offer effective control, their long-term use leads to increased fungicide resistance and poses risks to the environment and human health due to pesticide residues, underscoring the urgent need to develop novel fungicides. Artemisinin, first identified in Artemisia annua, is renowned for its antimalarial activity. Here, we demonstrate that artemisinin exhibites effective Antifungal activity against Sclerotinia sclerotiorum with an EC₅₀ value of 0.1 mg/mL. Treatment with artemisinin caused the mycelia surface to collapse and shrivel, accompanied by enhanced membrane permeability. Pretreating Brassica napus and Arabidopsis leaves with artemisinin increased resistance to S. sclerotiorum Infection. Proteomic analysis revealed that artemisinin treatment markedly downregulated the expression of key functional proteins in S. sclerotiorum, including Enzymes involved in oxalic acid biosynthesis, cell wall-associated proteins, and secreted proteins. In conclusion, artemisinin exhibits notable inhibitory effects against S. sclerotiorum and may hold potential for development as a novel fungicide.