A selective medium for isolation and identification ofBotrytis spp. from Soil and onion Seed

Abstract

The population ofBotrytis allii in either naturally or artificially infested soils was selectively measured by the soil dilution plate count procedure on a developed synthetic medium supplemented with tannic acid, fungicides, antibiotics and Cu⁺⁺ions. Conversion of tannic acid into a dark brown pigment was related to the activity of extracellular polyphenoloxidase produced by the fungus. Thus, brown-pigmented colonies were recognized asBotrytis spp. The same medium was used for detecting the presence of the fungus on onion seed.