A recently discovered species of Chromobacterium (C. suttsuga) produces toxins that are insecticidal to whiteflies and other pest species of insects. Nymphal and adult whiteflies fed on artificial diets containing an aqueous extract of C. suttsuga exhibited reduced percent survival and/or mean day survival. When fed on a diet containing 10% of a C. suttsuga extract, the number of 2nd, 3rd and 4th instar nymphs and emerged adults was significantly lower (15 – 34%) in experimental groups compared to control groups. Adult B. tabaci fed on artificial diet containing 5% of a cell-free bacterial preparation exhibited 100% mortality after 4 days. When subjected to fractionation through molecular weight cut-off filters, activity was present in the less than 30 kDa and greater than 100 kDa fractions. Activity of the lower molecular weight component(s) was partially reduced after prolonged storage at room temperature or drying and/or extraction in 50% methanol and was completely destroyed by boiling. In contrast, activity of the higher molecular weight component(s) was stable to the first three of these treatments and only slightly reduced after being subjected to boiling for 2 min. Thus, data support the existence of at least two toxins, the identities of which have not yet been determined.