GLUCANOLYTIC ACTINOMYCETES ANTAGONISTIC TO PHYTOPHTHORA-FRAGARIAE VARRUBI, THE CAUSAL AGENT OF RASPBERRY ROOT-ROT

A collection of about 200 actinomycete strains was screened for the ab ility to grow on fragmented Phytophthora mycelium and to produce metab olites that inhibit Phytophthora growth. Thirteen strains were selecte d, and all produced beta-1,3-, beta-1,4-, and beta-1,6-glucanases, The se enzymes could hydrolyze glucans from Phytophthora cell walls and ca use lysis of Phytophthora cells, These enzymes also degraded other glu can substrates, such as cellulose, laminarin, pustulan, and yeast cell walls, Eleven strains significantly reduced the root rot index when i noculated on raspberry plantlets.