ANTIFEEDANT EFFECT OF VARIOUS AQUEOUS LEAF EXTRACTS AGAINST TOBACCO CATERPILLAR, SPODOPTERA LITURA FAB.

Abstract

Indiscriminate use of pesticides for the management of insect pests has resulted in a number of biological and environmental hazards This man made intervention into the nature has further resulted in phytotoxicity, mammalian toxicity, pesticide residues, insect resistance, insect outbreaks and increased cost of production. Hence, the search for new solutions to control insect pests is currently gaining momentum (Scott et al., 2003). More than 1000 species of plants have been reported to have chemicals in leaves, stems, flowers, seeds and roots which have insecticidal property, only a few of them have been used for practical insect control on a commercial scale in the past. The chemical poisons of plants are mostly alkaloids. The alkaloid extracts when applied to the insects bring about disturbance in the nervous system and cause death. They are, therefore, basically act as nerve poisons (Shahid, 2003).