ANTIFUNGAL HYDROXYMETHYL-PHENOLS FROM THE MYCOPARASITE VERTICILLIUM-BIGUTTATUM

Secondary metabolites were extracted from culture filtrate of three is olates of the mycoparasitic biocontrol agent Verticillium biguttatum a nd two antifungal metabolites isolated using a standard TLC procedure. The structures of droxy-5'-(hydroxymethyl)phenyl]-3-methyl-but-2-ene and thoxy-5'-(hydroxymethyl)phenyl]-3-methyl-but-2-ene were elucidated by spectroscopic analysis. These new metabolites were named bigutol a nd methylbigutol, respectively. Low concentrations of each metabolite inhibited mycelial extension of Rhizoctonia solani (minimum inhibitory concentration 138 mu g ml(-l)) and other plant pathogenic fungi on po tato dextrose agar. Production of these antifungals by V. biguttatum s uggests that antibiosis may play a role during biocontrol by this myco parasite, particularly of plant diseases caused by R. solani.