Laboratory-based study on the predatory ability of Carabus yaconinus (Coleoptera: Carabidae) on larvae of Spodoptera litura (Lepidoptera: Noctuidae)

Abstract

We investigated the predatory ability of Carabus yaconinus (Coleoptera: Carabidae) on larvae of Spodoptera litura (Lepidoptera: Noctuidae) in the laboratory. A C. yaconinus adult preyed on ca. 90 S. litura larvae at the second-instar stage during 24 h. The number of larvae killed in 24 h decreased to ca. 40, 30 and 20 at third-, fourth- and fifth-instar stages, respectively. The wet weight of S. litura larvae killed by a C. yaconinus in 24 h increased with the larval stages of S. litura, and was highest for the fifth-instar stage. C. yaconinus adults occasionally left the predation unfinished and bit another live prey. The proportion of half-eaten prey varied with the larval stage of the prey. C. yaconinus can efficiently kill large numbers of S. litura larvae; thus, it may play an important role as a natural enemy of lepidopteran pests in agricultural fields.