Sensitivity of Coniella vitis in Shandong Province to mefentrifluconazole and three other triazole fungicides

In order to clarify the sensitivity of Coniella vitis to mefentrifluconazole, the sensitivity of 66 C. vitis isolates from 6 cities in Shandong Province to mefentrifluconazole was determined by the mycelial growth rate method. Additionally, the indoor and field control efficacy of mefentrifluconazole and three triazole fungicides, propiconazole, difenoconazole, and tebuconazole was compared. The results showed the population of C. vitis exhibited sensitivity to mefentrifluconazole, with effective inhibition concentrations (EC₅₀) ranging from 0.0210 to 1.9464 μg/mL and an average value of (0.7578 ± 0.4322) μg/mL. The sensitivity frequency is distributed in a continuous unimodal curve, conforming to a normal distribution. Therefore, the average EC₅₀ value can be considered as the baseline sensitivity of C. vitis in Shandong Province to mefentrifluconazole. The average EC₅₀ values of propiconazole, difenoconazole and tebuconazole against 31 randomly selected isolates were (1.1667 ± 0.4456), (2.1577 ± 0.5007) and (5.8187 ± 1.5538) μg/mL, respectively. The experiments showed the activity of mefentrifluconazole against C. vitis was comparable to that of propiconazole and difenoconazole, and better than that of tebuconazole. These findings provide a basis for monitoring pesticide resistance and effective control of C. vitis in fields.