Preimaginal conditioning affects oviposition choices in the silkworm moth (Bombyx mori)

Abstract

Nowadays we can find a number of experiments that have showed the importance of learning in several situations related with survival of many animal species. For instance, knowledge acquired in the early stages of life could be crucial on the choice of egg-laying site. In this study we explored the influence of Pavlovian conditioning of silkworm larvae on their oviposition behaviour as adult female moths. For this, the larvae learning have to survive the metamorphosis and be shown in oviposition choice. In acquisition phase, a larvae group experienced an odour (conditioned stimulus) paired with mulberry leaves (unconditioned stimulus), another one experienced the odour and the mulberry leaves in an unpaired way and the last one experienced the odour alone during this phase. The results show that when these larvae became moths, only the first group preferred to lay their eggs near the odour when it was present during the test, so that associations learned during the larval stage seem to influence oviposition behaviour during adulthood.

Keywords: Bombyx mori; Insect learning; Lepidopteran; Oviposition behaviour; Pavolovian conditioning; Preimaginal conditioning.