Rescue experiments for evaluating fungicide insensitive Phytophthora infestans isolates

During the year 2002 a Shirlan (Fluazinam) insensitive P. infestans isolate (# 69) was isolated in Germany which could not be stopped even by applying a higher fungicide concentrations. To show whether this isolate was still vital and pathogenic, a so called “rescue method” was performed. By using this rescue method it is not only possible to determine fungicide insensitivity in the lab, but also the remaining infectivity of P. infestans after treatment with the fungicide can be shown.