Characterization of Marine Actinomycete having Antiviral Activity against Cucumber Mosaic Virus

Metabolite of 28 marine actinomycete isolates was assessed for antiviral activities against cucumber mosaic virus (CMV). Metabolite of one isolate (no. 21) was found most effective in controlling the CMV infection under glasshouse conditions by dual inoculation, seed treatment and spray treatment, individually. Under field conditions, treatment of cucumber seeds with the metabolite of actinomycete isolate no. 21 followed by four foliar sprays of the metabolite on cucumber plants, effectively controlled CMV infection. The morphological structures of the isolate were identical to Streptomyces sp. It was identified as Streptomyces olivaceus on the basis of 16-S ribosomal RNA gene sequencing which was in conformity with morphological, physiological and biochemical characteristics of the isolate.