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Diabrotica spp. (Coleoptera: Chrysomelidae) beetles and southern green stink bugs, Nezara viridula (L.) (Heteroptera: Pentatomidae), are pests on corn, Zea mays L., and soybean, Glycine max (L.) Merr., as well as on cucurbits. Control of these insects has depended on chemicals. An alternative to chemical control is the use of biologicals. Use of bacteria, fungi, viruses, pheromones, and metabolites to control these insects can potentially improve resistance management and reduce pesticide use. Other than Bacillus thuringiensis Berliner, few bacteria have been discovered that are lethal to either of these pests. Chromobacterium subtsugae Martin et al., a newly described bacterium that is known to be toxic to Colorado potato beetle, Leptinotarsa decemlineata (Say), larvae, was found to be toxic to both diabroticite adult beetles and southern green stink bug adults. In laboratory assays, toxins produced by these bacteria kill 80–100% of the adults of two species of diabroticite beetles, Diabrotica undecimpunctata howardi Barber and Diabrotica virgifera virgifera LeConte, and 100% of southern green stink bug adults within 6 d. For green stink bug, live bacteria were not needed for toxicity.

A mixture of (E)-2-hexenal, a-terpineol, linalool, terpinen-4-ol, and benzyl alcohol attracts adults of the predaceous spined soldier bug, Podisus maculiventris (Say). The male-produced pheromone contains (+)-a-terpineol; however, (-)-a-terpineol is not inhibitory to the bug, so artificial pheromone can be made with racemic a-terpineol. Four parasitic species use the pheromone as a kairomone and two of these parasitoids are partially inhibited by (-)-a-terpineol. This is the first artificial long-range pheromone for a member of the true bugs (Hemiptera: Heteroptera) and the first such pheromone for a nonsocial predaceous insect.

Methyl (2E,4Z)-decadienoate was isolated and identified as the major male-specific volatile of Euschistus conspersus, E. tristigmus, E. servus, E. politus, and E. ictericus. In a sixth species, E. obscurus, this ester is a relatively minor male-specific component, with the major component being tentatively identified as methyl 2,6-dimethyltetradecanoate. Females, males, and nymphs of E. conspersus, E. tristigmus, E. servus, and E. politus were significantly attracted to methyl (2E,4Z)-decadienoate in field tests conducted in California and Maryland. Tests in Maryland also demonstrated that parasitic tachinid flies use the Euschistus unsaturated methyl-ester as a host-finding kairomone. It is not yet clear what role minor volatile components of Euschistus play in reproductive isolation.