Laboratory Measurement of Predation by Podisus maculiventris and P. sagitta (Hemiptera: Pentatomidae) on Beet Armyworm (Lepidoptera: Noctuidae)

Abstract

Predation rates for nymphs and adults of the predatory stink bugs, Podisus Maculiventris (Say) and Podisus sagitta (F.), on the different developmental stages of the beet armyworm, Spodoptera exigua (Hubner), were measured in the laboratory. Development and survival of predator nymphs also were monitored to evaluate prey suitability. The predators displayed high predation rates against different stages of the beet armyworm. However, eggs, first- and second-instar caterpillars, and adults of S. exigua proved to be less suitable prey for late instars and adults of both pentatomids. Predation rates of P. maculiventris were similar to or slightly higher than those of the smaller-sized P. sagitta. Results are discussed in relation to experimental conditions (searching arena, temperature) and quality of laboratory-reared predators.