Reproductive rate and predatory ability of the pentatomid bug, Andrallus spinidens (Fabr.) (Heteroptera: Pentatomidae)

Abstract

The pentatomid bug, Andrallus spinidens (F.), is a polyphagous predator on lepidopteran larvae in crop fields in southern Japan. The basic life history biology of the bug was studied using a laboratory incubator with temperature set at 25°C. The nymphs were reared in Petri dishes in groups of 10 and were fed on the 3rd-5th instar Spodoptera litura larvae. The mean development period from egg to adult was 32 d. The pre-oviposition period lasted 7 to 8 d, after which eggs were laid in batches every 2-3 d. The mean number of eggs per mass was 75.4 and the mean total number of eggs laid by each female was 499. The net reproductive-rate (R0), mean generation time (T) and intrinsic rate of natural increase (r) were 153.8, 49.8 d and 0.101/d/female, respectively. Groups of 10 nymphs attacked 4-8 of the 3rd-5th instar S. litura larvae per day. Pairs of adult pentatomids killed 3-5 of the 5th instar S. litura larvae weighing 450-550 mg each day. This study provides important life history information for using the predator A. spinidens as a possible biological control agent.