Effect of Prey and Predator Age on the Feeding Preference and Rate of Predation by Two Predators Coccinella transversalis Fab. and Cheilomenes sexmaculatus (Coleoptera: Coccinellidae)

The feeding preference of two coccinellid predators namely, Coccinella transversalis F. and Cheilomenes sexmaculatus F. on different instars and forms of the aphid, Aphis gossypii Glov. and predator age-dependent interference on the rate of predation were investigated. Significant differences were observed among the predatory stages for various prey ages. Older predators fed on older preys. However, adult beetles did not show any marked preference and fed on all stages and forms of preys. The various combinations of adults and grubs at different levels significantly affected the prey consumption levels. Among the various treatments, the treatment with 12 predators consumed the maximum number of aphids at all prey levels followed by 12 adults + one instar grub indicating the addition of a grub did not increase the prey consumption of adults.