Functional Response of an Assassin Bug Rhynocoris kumarii Ambrose and Livingstone (Insecta: Hemiptera: Reduviidae) to Odontotermes Brunneus (Hagen) (Insecta: Isoptera: Termitidae)

Abstract

The functional response of the assassin bug, Rhynocoris kumarii Ambrose and Livingstone to Odontotermes brunneus (Hagen) was investigated. Different levels of termite densities - 1, 2, 4, 8, 16 and 32 were used. Each density was placed in a test cage (14 x 22 x 10cm) and then exposed to 24hr starved fourth and fifth nymphal instars and adult males and females of R. kumarii under laboratory conditions (28-34°C temperature; 12 ± 1hr. photoperiod; 65-70 relative humidity). All the experimental life stages of R. kumarii responded to the increasing prey density of O. brunneus by killing a greater number of preys than at lower prey densities. Thus, the predators exhibited the type II curvilinear functional response. The maximum predation (K) was restricted to high prey density (24.889, 24.722, 22.889 and 24.194 for IV, V nymph and adult male and female respectively). The searching capacity of R. kumarii increased with increasing termite density and this reflected its predatory potential.