Disclosed is a pesticide formulation comprising a whole cell broth, filtrate, supernatant, or extract of a strain of Chromobacterium species containing a the metabolites violacein, deoxyviolacein, or chromamide A. The formulation is used in methods for modulating pest infestations. Also disclosed is the addition of a stabilizing agent such as a benzoic acid salt or lignosulfonate salt to the presticide formulation to give an improved shelf life due to maintenance of physical uniformity and longer insecticide activity after use due to higher resistance to degradation when exposed to sunlight.
