A LABORATORY TECHNIQUE TO STUDY A CHANGE IN FEEDING BEHAVIOR BETWEEN SMALL AND LARGE LARVAE OF GYPSY MOTH, LYMANTRIA DISPAR (L.)

Abstract
A change in the feeding behavior between small and large larvae of gypsy moth, Lymantria dispar (L.), is an important part of the insect’s biology. This paper describes how to build a lighting system with incandescent and fluorescent light in the laboratory to induce a change in feeding behavior similar to the change that occurs in the field. The change in feeding behavior was observed on artificial “tree stems” constructed from 5-cm ABS plastic pipe and fitted with felt and cardboard “bark flaps”. On the day before pupation began, 85% of the population migrated down the artificial tree stems to seek shelter under the bark flaps; only fourth-, fifth-, and sixth-instar larvae were observed exhibiting this behavior.