Potential for integrating eleven agricultural insecticides with the predatory bug Pristhesancus plagipennis (Hemiptera: Reduviidae)

A problem for growers attempting to implement integrated pest management programs is the lack of information regarding the compatibility of insecticides with natural enemies. To provide information about this problem, we evaluated the acute and residual effects of 11 commonly used insecticides on nymphs of Pristhesancus plagipennis (Walker) under both laboratory and field conditions. For each insecticide, the length of time that weathering residues caused > 50% mortality was evaluated and compared against the LC50 (acute-toxicity) divided by the recommended field rate. Plots thus combined the acute and residual toxicity of each insecticide. Results suggested that carbaryl, esfenvalerate, endosulfan, and deltamethrin had low residual and acute toxicity to P. plagipennis, whereas chlorpyrifos, methomyl, and monocrotophos were highly toxic at low concentrations and left persistent harmful residues. Cypermethrin, methidathion, malathion, and dimethoate were moderately toxic. The potential use of these insecticides to supplement the control activity of P. plagipennis is discussed.