Mefentrifluconazole-Resistant Risk and Resistance-Related Point Mutation in FpCYP51B of Fusarium pseudograminearum

Abstract

Mefentrifluconazole, a triazole fungicide, exhibits remarkable efficacy in combating Fusarium spp. The mean EC50 value of mefentrifluconazole against 124 isolates of Fusarium pseudograminearum was determined to be 1.06 μg/mL in this study. Fungicide taming produced five mefentrifluconazole-resistant mutants with resistance factors ranging from 19.21 to 111.34. Compared to the original parental isolates, the fitness of three resistant mutants was much lower, while the remaining two mutants displayed enhanced survival fitness. There was evidence of positive cross-resistance between tebuconazole and mefentrifluconazole. Mefentrifluconazole resistance in F. pseudograminearum can be conferred by FpCYP51BL144F, which was identified in four mutants according to molecular docking and site-directed transformation experiments. Overexpression of FpCYP51s was also detected in the resistant mutants. In conclusion, mefentrifluconazole has a low-to-medium resistance risk in F. pseudograminearum, and the L144F mutation in FpCYP51B and the increased expression level of FpCYP51s may be responsible for mefentrifluconazole resistance in F. pseudograminearum.

Insights into the Enantiomeric Uptake, Translocation, and Distribution of Triazole Chiral Pesticide Mefentrifluconazole in Wheat (Triticum aestivum L.)

“…Racemates of MFZ (Rac-MFZ) consist of equal amounts of enantiomers R-(−)-MFZ and S-(+)-MFZ . Up to now, research on MFZ mainly focuses on chiral separation, , biological toxicity, ,,, residual analysis, and resistance risk . For example, Li et al separated the two enantiomers of MFZ via Chiral MX (2)RH column and established analytical methods in six plant matrices using UPLC-MS/MS .…”