1National Bureau of Agriculturally Important Insects, Post Bag No. 2491, H. A. Farm Post, Hebbal, Bellary Road, Bangalore 560024, Karnataka, India.
2Shrimathi Indira Gandhi College, Tiruchirappalli 620002, Tamil Nadu, India.
3Department of M.C.A., Shrimathi Indira Gandhi College, Tiruchirappalli 620002, Tamil Nadu, India.
4Indian Institute of Horticultural Research, Hessaraghatta Lake Post, Bangalore 560089, Karnataka, India.
5Department of Entomology, Agricultural Research Station, Raichur 584101, Karnataka, India.
*Corresponding author E-mail: mpratheepa@rediffmail.com
An attempt was made to study the effect of abiotic and naturally occurring biotic factors on Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) with cotton as a model crop system. The results revealed that Chrysoperla sp. (carnea-group) (r = 0.344) was positively correlated with pest incidence and the weather parameters like maximum temperature (r = -0.309) and rainfall (r = -0.288) were negatively correlated with pest incidence. It was observed that post-monsoon season was most favourable for pest occurrence and it was more when the crop was in flowering and boll formation stage. Spiders and Chrysoperla sp. (carnea-group) were positively correlated with pest incidence during winter.
Helicoverpa armigera, cotton, season, spiders, chrysopids
