Negative cross‐resistance toN‐phenylanilines in benzimidazole‐ resistant strains ofBotrytis cinerea,Venturia nashicolaandVenturia inaequalis

摘要

AbstractA new series of compounds with high contra‐selective activity against benomyl‐resistant fungal strains was found among ring‐substitutedN‐phenyl‐anilines. Hydrophobic substitution in one of the benzene rings, together with the secondary amine character of the molecule, are important factors for high fungitoxicity. The sensitivities of benomyl‐resistant isolates to some representatives of theN‐phenylanilines equal or even surpass their sensitivity to diethofencarb or MDPC. The negative cross‐resistance with benzimdazole fungicides is valid for strains ofBotrytis cinerea,Venturia nashicolaandVenturia inaequalis. The strains ofB. cinereawith double insensitivity to benzimidazoles and phenyl‐carbamates are insensitive also toN‐phenylanilines. However, the similarly double‐insensitive strain ofV. nashicolawas found to be just as sensitive to theN‐phenylanilines tested as the strain resistant only to benzimidazoles. The latter result revealed an important bonus compared with diethofencarb. Preventive application of one of the most active representatives of theN‐phenylanilines to young cucumber plants was effective against infection with benomyl‐resistant isolates ofB. cinerea. Moderate apical translocation after roo