Fungicide resistance in Botrytis cinerea isolates from strawberry crops in Huelva (southwestern Spain)

The severity of disease caused by Botrytis cinerea in strawberries is very high and chemical control is common practice; low residue levels of chemical products are required. Thus, it is important to be aware of the development of fungicide resistance in order to choose the best strategies of chemical control. In the present study we evaluated the response of 36 B. cinerea isolates against eight different fungicides. The isolates were sampled twice, at the beginning and the end of the season, in I I commercial strawberry fields located in the area of Huelva (Spain).. In addition, two reference isolates, SAS56 and SAS405, were evaluated. The proportion of isolates resistant to benomyl was very high (86%). Resistance to dicarboximides was detected in 44% of the isolates and resistance to pyrimethanil in 25% of the isolates. Different degrees of sensitivity to captan and dichlofluanid were recorded. No resistance was found to diethofencarb plus carbendazim.