Antagonists of Fomes annosus in the rhizosphere of grey alder (Alnus incana) and Norway spruce (Picea abies)

A comparison was made of the fungistatic effects of the root microflora of grey alder and Norway spruce with Fomes annosus as test fungus. The significantly higher frequency of actinomycetes in the alder rhizosphere probably constituted the main difference in this respect. The importance of fungi seemed to be about equal in the rhizosphere of the two tree species. Methods for studies of antagonism are tested and discussed.