Resistance risk to new botryticides in Botrytis cinerea Pers.:Fr. in winegrowing areas in Croatia

The problem of Botrytis cinerea Pers.:Fr. resistance phenomena, especially pronounced in the protection of vineyards, restricted the use of many fungicides. But, chemical control remains the only way to reduce the incidence of grey mould in grapevine caused by B. cinerea. In order to overcome the problem of resistance there are continuous world efforts to develop new active ingredients. During the last decade new active ingredients have been developed in the world, of which pyrimethanil and cyprodinil from anilinopyrimidine group were acknowledged in Croatia in 1997, and fenhexamid (hydroxianilide) in 1998. The goal of this investigation was to monitor the presence of strains resistant to the mentioned ingredients in field populations of B. cinerea in vineyards in which those ingredients had been applied intensively since 1997. The paper presents confirmation of existence of pyrimethanil and cyprodinil resistant subpopulations and first reports fenhexamid resistant strains in Croatia.