Deoxynivalenol in : Evaluation of Cyproconazole Stereoisomers and .

Cyproconazole (CPZ), a representative chiral triazole fungicide, is widely used to control Fusarium head blight (FHB). In this study, the stereoselective efficiency of CPZ was investigated and . Consistent results were observed between the bioassay and the visual disease rating, with the control efficacy ordered RS-CPZ > RR-CPZ > SR-CPZ > SS-CPZ. Unexpectedly, the deoxynivalenol level was in the order RR-CPZ > RS-CPZ > SS-CPZ > SR-CPZ, while RS-CPZ inhibited the deoxynivalenol production and ergosterol biosynthesis in . We further investigated that the genes were upregulated in of the RS-CPZ group, and SR-CPZ preferentially degraded in wheat. An extra action mode of CPZ was inferred to stimulate the production of deoxynivalenol. These findings revealed the stereoselective efficiency of CPZ stereoisomers against FHB and provided new insights into the mechanism of action of triazole fungicides against FHB and deoxynivalenol.