Evaluation of meridic diets suitable for efficient rearing of Heliothis virescens (F.) (Lepidoptera: Noctuidae)

Abstract

Heliothis virescens, which attacks the cotton reproductive structures, is considered one of the main pest of this crop in the Americas. Therefore, it is necessary to evaluate, monitor and develop new control techniques, under laboratory conditions. Artificial diets can facilitate these tasks, besides being of low cost and independent of the host plant. In this research three merídic diets, ICRISAT diet 3, modified Greene and modified Shorey & Hale, as well as a natural one, green beans, were evaluated through three consecutive insect’s generations. The H. virescens population evaluated originated form larvae collected in Desmodium sp. at El Espinal, Department of Tolima in Colombia. All diets allowed the rearing of the larval stages showing differences in the developmental time, as well as in the life cycle, the survival, and the larval and the pupal weight. The most promising diet was ICRISAT diet 3, producing a shorter larval developmental time, a lower number of instar stages, highest larval and pupal weights and a near 70% survival up to the adult stage. However, the initial positive characteristics diminished through subsequent insect generations, so it is recommended to improve this diet or to evaluate others which can be used through more continuous generations.