ISOLATION AND PARTIAL-PURIFICATION OF A PHYTOTOXIN RELATED TO PATHOGENIC VERTICILLIUM SPECIES

The low molecular weight metabolites are considered as phytotoxins of pathogenic Verticillium species. The resin, Amberlite XAD-4 was used f or isolation of toxin from log-phase culture fluids of the fungus. The toxin was purified further using gel permeation. The isolated toxin i nduced chlorosis and necrosis in detached-leaflets of susceptible toma to and potato cultivars similar to natural symptoms. The metabolite is polar, multifunctional, heat stable, cold labile with molecular weigh t less than 1000. The activity was retained in dried samples of the cr ude filtrate and kept at room temperature for up to 8 months.