Distribution of fungicide-resistant Botrytis cinerea mutations in the Tokaj and Eger wine regions

Abstract

Botrytis cinerea is one of the most widespread host-specific fungal pathogens, causing significant yield losses and economic damage to vineyards every year. As a widespread, polyphagous fungal pathogen, it is capable of living a saprophytic or parasitic lifestyle. The successive use of active substances belonging to the same chemical family to protect vineyards may result in an increase in fungal resistance to chemicals, which is reflected in the amplification of point mutations in the genomic regions coding for proteins involved in the mechanism of action of different pesticides. The aim of our study was to compare the fungicide susceptibility of Botrytis cinerea populations in two wine regions with different pest management practices: in Tokaj, where the presence of Botrytis cinerea is necessary for the production of noble rot wines, and in neighbouring Eger, where a comprehensive strategy for the prevention of Botrytis cinerea is followed. This study is the first presentation in Hungary of some previously documented resistance mutations in the ERG27 and SDHB protein coding genes. Our results revealed the presence of point mutations in the transmembrane domain of ERG27 that have not been previously described in the literature. These mutations may potentially influence the development of resistance to specific fungicides. Our studies show that the Botrytis cinerea population in the Northern Hungary region consistently shows an increase in fenhexamid resistance.