Comparison of Perillus bioculatus and Podisus maculiventris (Hemiptera: Pentatomidae) as potential control agents of the Colorado potato beetle (Coleoptera: Chrysomelidae)

In laboratory and microplot consumption tests, spined soldier bug, Podisus maculiventris (Say), ate at least as many Colorado potato beetle, Leptinotarsa decemlineata (Say), eggs and larvae as did the twospotted stink bug, Perillus bioculatus (F.). P. maculiventris also remained in field microplots infested with Colorado potato beetle egg masses for slightly longer than did P. bioculatus. The 2 predators were equally effective at consuming egg masses, reducing densities of beetle larvae, and preventing potato defoliation in small field plots. These results contrast with previous trials, in which P. bioculatus had been more effective. In laboratory trials, larger P. maculiventris nymphs selected larger prey larve whereas P. bioculatus nymphs did not discriminate by size of prey; thus, the relative effectiveness of the 2 predators may depend on the life stages of the prey that are present at the time of predator release.