SCREENING OF ANTAGONISTIC FUNGI AGAINST AIR-BORNE INFECTION BY HETEROBASIDION-ANNOSUM ON NORWAY SPRUCE

In vitro inhibition of Heterobasidion annosum by fungi isolated from t he surface and inside of Norway spruce (Picea abies L.) stumps, ten Ve rticillium bulbillosum strains from Fagus sylvatica L. mycorrhizoplane , and three lignivorous basidiomycetes from culture collections was ev aluated at 5, 10 and 15 degrees C in a search for potential biocontrol candidates. Forty-nine strains from nine genera and hyaline sterile m ycelia with or without clamp connections were isolated from spruce. Ov er 50% inhibition at one or more temperatures was displayed by 21 of 4 9 isolates. Fresh wood tests were also performed with the six fungi th at displayed the highest in vitro activity and with the basidiomycetes . The best results were observed with Hypholoma fasciculare, Trichoder ma harzianum 7/AO, Verticillium bulbillosum (culture filtrate) and Pha nerochaete velutina.