Biological Control of Fusarium oxysporum f. sp. melonis, the Causal Agent of Root Rot Disease of Greenhouse Cucurbits in Kerman Province of Iran

Antagonistic activity of 178 soil actinomycete isolates was assayed against Fusarium oxysporum f. sp. melonis Schlecht, Emend (Snyde and Hansen) cause of root rot and fusarium wilt of greenhouse cucurbits in Kerman Province, southeast of Iran. From tested isolates, Streptomyces olivaceus (strain 115) showed anti-fusarium activity revealed through screening and bioassays by agar disk and well-diffusion methods. The active strain was grown in submerged cultures for determination of growth curve and preparation of crude extract for further biological characterizations. Antifungal activity was fungistatic type on the pathogen mycelia. It is prominent that amending greenhouse soil mix with the S. olivaceus (strain 115) will reduce crop losses by the pathogen.