INFLUENCE OF TEMPERATURE ON DEVELOPMENT OF PINK BOLLWORM, Pectinophora gossypiella (Saunders) LARVAE

Abstract

Pink bollworm, Pectinophora gossypiella (Saunders) a pest of cotton having national importance, recently became serious on BG II cotton
hybrids, causing damage from flowering stage onwards by feeding on anthers and pollen and living in a sort of web. Such flowers are  characteristically twisted in the form of rose called as rosette flower. Later the larvae bore into the green bolls, and further burrow into mature bolls through the lint penetrating deep into seeds. When one seed is destroyed, the larvae tunnel and enters through the developing lint and migrates to another seed and similarly to locules. The affected bolls rot and shed, while those retained on plants open prematurely resulting in stained immature fibre, causing 80 percent reduction in seed cotton yield and quality of lint (Henneberry and Clayton 1986). Pupation of PBW
occurs in flimsy cocoon in the boll, often in seed hollowed out by larva or in soil. Pink bollworm has a tendency to enter into facultative diapause in some temperate and tropical regions of the world. Induction and termination of diapause depends on the seasonal changes such as temperature, photoperiod, availability of food etc. Present study was conducted to define the influence of temperature on development of pink
bollworm.