Chromobacterium subtsugae strain PRAA4-1T.jpg

Chromobacterium subtsugae strain PRAA4-1T

Chromobacterium subtsugae strain PRAA4-1T is a gram-negative, violet-pigmented bacterium that was isolated from soil under an eastern hemlock (Tsuga canadensis) in the Catoctin Mountain region of central Maryland. The United States Department of Agriculture found this isolate of Chromobacterium subtsugae to be orally toxic to Colorado potato beetle (Leptinotarsa decemlineata) larvae, small hive beetle (Aethina tumida) larvae, southern corn rootworm (Diabrotica undecimpunctata) larvae and adults, and southern green stink bug (Nezara viridula) adults. Additional testing has shown that Chromobacterium subtsugae strain PRAA4-1T-treated diet resulted in reduced feeding in beet armyworm (Spodoptera exigua), cabbage looper (Trichoplusia ni), tobacco budworm (Heliothis virescens), diamondback moth (Plutella xylostella), and southern corn rootworm, suggesting this microbe’s insecticidal activity is due to reduction in weight or inhibition of feeding.

GRANDEVO® is a biological insecticide/miticide containing fermentation solids of Chromobacterium subtsugae strain PRAA4-1T for use on edible crops against the pests listed in the Directions for Use section. GRANDEVO® can be used in the field or greenhouse for the control of any labeled pest.

Target Pests: armyworms, cutworms, aphids, psyllids, whiteflies, Lygus and mealybugs, and on thrips and phytophagous mites such as spider mites, broad mites, russet mites and rust mites.

Application Rate Instructions

Watch the effects Grandevo has on the twospotted spider mite

Mode of Action:  GRANDEVO® functions primarily as a stomach poison for use in the control or suppression of many foliar-feeding pests, including caterpillars, and certain coleopteran. GRANDEVO® has multiple effects, including reducing fecundity and oviposition, deterring feeding and acting as a stomach poison on Homoptera and Hemiptera, such as aphids, psyllids, whiteflies, Lygus and mealybugs, and on thrips and phytophagous mites infesting labeled crops or use sites.

Application Tips: Close scouting and early attention to infestations is highly recommended. For insects and mites, proper timing of application targeting new populations or recently hatched larvae and nymphs is important for optimal results. Applying GRANDEVO® when pest populations are low is recommended. GRANDEVO® must be mixed with water and applied as a foliar spray with ground or aerial equipment equipped for conventional insecticide spraying or by chemigation.

Repeat applications at an interval sufficient to maintain control, depending upon plant growth rate, insect and mite activity, and other factors. If attempting to control an insect population with a single application, make the treatment when egg hatch is essentially complete but when larvae or nymphs are young and before economic damage occurs.

To enhance control, consider tank mixing with contact insecticides/miticides. Use the lower label rates of GRANDEVO® when populations are low and when tank mixing with other insecticides/miticides. Use the higher rates of GRANDEVO® when applied stand-alone, when populations are high or when egg numbers are high.

For hard-to-wet crops, consider using a spreader/sticker or adjuvant, which has been approved for targeted crop use, to enhance coverage and adhesion of GRANDEVO® to the crop.

GRANDEVO® has been evaluated for phytotoxicity on a variety of crops under various normal growing conditions. However, testing all crop varieties, in all mixtures and combinations, is not feasible. Prior to treating entire crop, test a small portion of the crop for sensitivity.

Precautions and Safety Equipment:


Applicators and other handlers must wear:

●  long-sleeved shirt and long pants

●  waterproof gloves

●  shoes plus socks

●  protective eyewear

Mixer/loaders and applicators must wear a dust/mist filtering respirator meeting NIOSH standards of at least N-95, R-95, or P-95. Repeated exposure to high concentrations of microbial proteins can cause allergic sensitization. Follow the manufacturer’s instructions for cleaning/maintaining PPE. If no such instructions for washables are available, use detergent and hot water. Keep and wash PPE separately from other laundry.

Water Quality Rating

  • Do not apply directly to water, or to areas where surface water is present or to intertidal areas below the mean high water mark. Do not contaminate water when disposing of equipment washwater or rinsate.

Impact on Natural Enemies

  • This product is toxic to certain non-target terrestrial arthropods. Minimize spray drift away from target area to reduce effects to non-target insects.

Impact on Honey Bees

  • This product is toxic to bees exposed to direct treatment or residues on blooming crops or weeds. Do not apply this product if bees are visiting the treatment area.

    This product is toxic to aquatic invertebrates. Drift and runoff may be hazardous to aquatic organisms in water adjacent to treated areas.



Selected References

EPA. BIOPESTICIDES REGISTRATION ACTION DOCUMENT. Chromobacterium subtsugae strain PRAA4-1T Pesticide Chemical (PC) Code: 016329