Decrease of Venturia inaequalis (cook) ADERH. Sensitivity to ergosterol biosynthesis inhibitor and dodine fungicides

摘要

The ergosterol biosynthesis inhibitor (EBI) and dodine fungicides are well known and have been used frequently for many years in the control of apple scab in Poland. An obvious decrease of effectiveness of fenarimol and dodine was observed in 1998 and 1999 in apple orchards treated with these compounds several times during the last few seasons. The monitoring of dodine resistance conducted in commercial apple orchards in the Warka and Grojec region in 1999 showed in some cases a high level (more than 50 percent) of dodine-resistant strains in the population of Venturia inaequalis and the occurrence of 5 to 30 percent of dodine-resistant strains in its population in the majority of checked orchards.