Effect of Chitin Synthesis Inhibitor, Lufenuron 5.4 EC on Cotton Bollworm Helicoverpa armigera (Hubner)

摘要

Field experiments were conducted during November 2011 to August 2012 at Narashimmanaiyakenpalayam and Pujanganoor, Coimbatore District, Tamil Nadu to evaluate the efficacy of Lufenuron 5.4 EC at 20, 30, 40 and 60 g a.i./ha. against Helicoverpa armigera (Hubner). In the two field experiments, Lufenuron 5.4 EC applied at 60 g a.i. ha~(-1) reduced the incidence of H. armigera by 86.83 and 85.37 per cent respectively over untreated control after three rounds of spraying. The highest yields of 20.58 q ha~(-1) and 16.25 q ha~(-1) were obtained in the plots treated with Lufenuron 5.4 EC at 60 g a.i. ha~(-1) at two locations followed by Lufenuron 5.4 EC at 40 g and 30 g a.i. ha~(-1).