All India Co-ordinated Cotton Improvement Project, R.R.T.T.S.S. Umerkote-764 073, District Nawarangpur, Orissa, India.
*Present address: AICP on Honey Bee Research and Training, Department of Entomology, College of Agriculture, O.U.A.T., Bhubaneswar, Orissa.
The life table studies of spotted bollworm Earias vittella (Fab.) on cotton were conducted for three generations corresponding to the vegetative and early flowering, peak flowering and fruiting and boll development and maturation stages of the crop. Based on ‘K’ values, unknown factors (predation and adverse climatic factors) were identified as key mortality factors during larval phase II of E. vittella. The natural enemies viz., Trichogramma chilonis and Rogadinae sp. also contributed some degree mortality in the pest population. The negative values of trend index (<1) in all the generations of the pest during both the years revealed that the mortality factors were effective in causing decline in pest population. The generation survival values ranged from 0.071 to 0.122.
