Studies on the effect of zuelaemycin producing actinomycetes strain S--5120 on downy mildew of cucumber

S-5120 strain and zuelaemycin with strong antagonistic against Psudoperonospora cubensis Berk.et Curt. were tested by using an spore-germination method and an method on detached-leaves.The protective effect and therapeutic effect of S-5120 strain on downy mildew of cucumber were tested in greenhouse.Respectively the protective effect of S-5120 strain was 75.17%,and the therapeutic effect was (69.69%) which was higher than that of 2% Nongkang-120 with 62.65%.