Crucial Roles of the High-Osmolarity Glycerol Pathway in the Antifungal Activity of Isothiocyanates against .

Isothiocyanates (ITCs) that are found in Brassicaceae exhibited obvious antifungal activity against , which is the causal agent of southern corn leaf blight. However, the underlying antifungal mechanism of allyl-ITCs (A-ITCs) against remains largely unknown. Here, we used transcriptomic analysis to find that the high osmolarity pathway was upregulated significantly when treated with A-ITCs. To investigate the roles of the high osmolarity pathway in adaption to A-ITCs, we constructed Δ, Δ, and Δ mutant strains. Deletion of three genes (, , and ) involved in the high osmolarity pathway resulted in significantly increased sensitivity of to ITCs. In addition, the phosphorylation level of ChHog1 was induced by A-ITC and was dependent on the presence of ChSsk2 and ChPbs2. Moreover, Δ, Δ, and Δ mutants exhibited a dramatically decreased virulence on maize leaves. Our findings demonstrated that the high osmolarity pathway played a positive role in ITC tolerance and virulence, which may provide novel insights into developing ITCs as a new fungicide against .