The Study on the Roles of Predators on Asian Corn Stem Borer, Ostrinia furnacalis Guenee (Lepidoptera: Pyralidae)

Abstract

The study aimed to investigate the role of predators in preying the larvae and pupae of corn stem borer, Ostrinia furnacalis Guenee (Lepidoptera: Pyralidae) was conducted in the farmer corn field during 2011. Two plant hills each of which 6 meter away were prepared one of which unglued and the other one glued for ground and canopy predators. On each plant, 5 larvae instar-2 and or -3 were made available (2 larvae at internode near the ground surface, 1 near the corn ear, at internode between ear and tassel and at the upper top internode respectively). The experiment was carried out with 10 replications so there were 20 plant hills prepared. The experiment was also carried out with the same procedures for pupae. The predators, visit frequency and the number of preys consumed by predators were recorded. The results indicated that there were 5 groups of predators i.e., ants, spiders, cricket, Coccinella sp., Chrysopa sp. and Paederus sp. were found to visit larvae and pupae on plant corn. The ant predator visit more frequently the prey larvae and pupae on both unglued and glued plants and only this predator recorded to prey larvae with the mean of 2.5 (50%) and 1.9 (38%) and pupae with the mean of 3.2 (64%) and 3.0 (60%) in 14 h period on glued and un-glued plants respectively. The ant, Solenopsis sp. found in this study can really be promoted as bio-logical control for Asian corn borer.