Dimethomorph and metalaxyl sensitivity in somatic hybrids of Phytophthora parasitica obtained by protoplast fusion

Protoplasts were successfully isolated from wild-type and mutant strains of #Phytophthora nicotianae$ var. #parasitica$ using Novozym 234. Putative somatic hybrids were recovered following protoplast fusions from the first time to dimethomorph resistant strain P 310 (Dim r) or metalaxyl P 26 (Met r) by selection on agar amended with dimethomorph and metalaxyl. Fusion products from this cross were resistant to dimethomorph and metalaxyl. Zoospore progeny from the fusion products retained this phenotype, suggesting that nuclear fusion had taken place. (Résumé d'auteur