Monitoring rezistence Venturia inaequalis k pyrimethanilu a strobilurinům v ČR v letech 2019 a 2020 [Monitoring of Venturia inaequalis resistance to pyrimethanil and strobilurins in the Czech Republic during 2019 and 2020]

Abstract

Apple scab, which is caused by the fungus Venturia inaequalis, is one of the most important diseases of apple trees. It mainly affects leaves, fruits, and sometimes also flowers and shoots. The aim of this work was monitoring the resistance of Venturia inaequalis to pyrimethanil and stobilurins fungicides. Part of our work included evaluation of the monitoring and assignment of the population to the relevant category of resistance to the active substances. A total of 46 populations were tested. Our results show that the population of V. inaequalis was generally more sensitive to pyrimethanil while resistant to strobilurins. A large percentage of the populations (76 %) was sensitive to pyrimethanil and just 1 was moderately resistant, only 31 % of the population was sensitive to strobilurins and 62 % were resistant.

Keywords

• resistance
• apple tree
• sensitivity
• apple scab