Resistance Risk and Current Status
Benzimidazoles represent the beginning of serious resistance problems in fungicides. A few years after commercialisation, loss of disease control with benzimidazole fungicides was recorded in many crops, especially with pathogens having numerous cycles per year, such as Botrytis cinerea. For pathogens having only 1-2 cycles per year, resistance developed after a longer period of use, e.g., more than 10 years for cereal eyespot caused by Tapesia spp. Nevertheless, benzimidazoles are still used widely and continue to be valuable fungicides in global agricultural production.
Since commercialization resistance to benzimidazoles has been reported in approximately 60 genera in over 115 species of fungi. Table 1 gives an overview of published information relative to resistance development in pathogenic fungi affecting economically important crops globally.
Cases of resistance to benzimidazole on key pathogens in economically important crops.
For a more detailed list of cases of resistance to benzimidazoles and other fungicides, see the List of Resistant Plant Pathogenic Organisms - February 2013.
Please send any additions or corrections about these tables to Jean-Luc Genet at Jean-Luc.Genet@dupont.com.