The beet armyworm, Spodoptera exigua, is one of the worldwide distributed agricultural pest insects and has been known to show high resistance to conventional chemical insecticides. Since it has been reported that secondary metabolites from actinomycetes show insecticidal activities against various insect pests, actinomycetes could be a potential source of insecticidal compounds. In this study, culture extracts of Streptomyces strains were tested for their insecticidal activity against Spodoptera exigua. Among them, culture extracts of IMBL-0003 strain which was identified as Streptomyces celluloflavus showed a high insecticidal activity (more than 90% mortality). These results suggested that secondary metabolites of this isolate could have potentials to be a efficient eco-friendly pesticide for controling Spodoptera exigua.

• Minghui Wang(Department of Agricultural Biotechnology, Seoul National University) Corresponding author
• Jae Young Choi(Research Institute for Agriculture and Life Sciences, Seoul National University)
• Dong Hwan Park(Research Institute for Agriculture and Life Sciences, Seoul National University)
• Siyi Liu(Department of Agricultural Biotechnology, Seoul National University)
• Yeon Ho Je(Department of Agricultural Biotechnology, Seoul National University, Research Institute for Agriculture and Life Sciences, Seoul National University)