Favorable Bioactivity of the SDHI Fungicide Benzovindiflupyr Against Mycelial Growth, Sclerotial Production, and Myceliogenic and Carpogenic Germination of Sclerotia.

, which can cause Sclerotinia stem rot, is a prevalent plant pathogen. This study aims to evaluate the application potential of benzovindiflupyr, a new generation of succinate dehydrogenase inhibitor (SDHI), against . In our study, 181 isolates collected from different crops (including eggplant [ = 34], cucumber [ = 27], tomato [ = 29], pepper [ = 35], pumpkin [ = 32], and kidney bean [ = 25]) in China were used to establish baseline sensitivity to benzovindiflupyr. The frequency distribution of the 50% effective concentration (EC) values of benzovindiflupyr was a unimodal curve, with mean EC values of 0.0260 ± 0.011 μg/ml, and no significant differences in mean EC existed among the various crops ( > 0.99). Benzovindiflupyr can effectively inhibit mycelial growth, sclerotial production, sclerotial shape, and myceliogenic and carpogenic germination of the sclerotia of . In addition, benzovindiflupyr showed good systemic translocation in eggplant. Using benzovindiflupyr at 100 μg/ml yielded efficacies of 71.3 and 80.5% for transverse activity and cross-layer activity, respectively, which were higher than those of acropetal and basipetal treatments (43.6 and 44.7%, respectively). Greenhouse experiments were then carried out at two experimental sites for verification. Applying benzovindiflupyr at 200 g a.i. ha significantly reduced the disease incidence and severity of Sclerotinia stem rot. Overall, the results demonstrated that benzovindiflupyr is a potential alternative product to control Sclerotinia stem rot.