The microbial insecticide Burkholderia spp

A novel bacterium Burkholderia spp. was isolated from a soil sample and is being developed into a microbial bioinsecticide by Marrone Bio Innovations. Whole cell broth of this microbial insecticide shows good activity against a wide variety of insect species in laboratory and greenhouse bioassays. Field trials with formulated material have also shown notable control against many insects. This bacterium produces multiple active secondary metabolites. One of these compounds was purified and it has a molecular weight of 540. The lethal median dose (LD50) of this compound against 3rd instar larvae of Cabbage looper Trichoplusia ni (Hübner) is less than 0.1µg per individual by topical application. Studies are underway to identify all active secondary metabolites, to optimize fermentation medium for metabolite production and to enhance efficacy via formulation development.