Influence of Habitat on Helicoverpa armigera (Hubner) in Cotton-ecosystem
Incidence and damage of Helicoverpa armigera (Hubner) were low in cotton in habitat with intercrops like groundnut, soybean, cowpea, mungbean and Setaria compared to sole cotton situation. Pigeonpea as intercrop was established to be unsuitable. Even though Setaria decreased the H. armigera incidence, it affected the growth and yield of cotton. The increased interspecific competition vis-a-vis environmental resistance by preserving natural enemies of H. armigera was evident when habitat was manipulated by maintaining intercrops in cotton.