Seasonal incidence of major insect pests and their correlation with weather parameters in cotton

The incidence of aphids was highest (21.2 aphids/three leaves) during 46th MW. Jassid's highest population (20.4 jassids/three leaves) was observed during 44th MW. Thrips reached highest incidence (37.80 thrips/three leaves) in 43rd MW. Highest incidence of whitefly (25.30 whiteflies/three leaves) was noticed during 42nd MW. The larval population of Helicoverpa armigera was highest (6.80 larvae/plant) in 45th MW. Per cent rosette flowers due to P. gossypiella was highest (36.10%) in 42nd MW. Larval population of P. gossypiella was highest (51 larvae/20 green boll) in 46th MW and per cent green boll infestation due to P. gossypiella is highest (95%) in 46th MW. Simple correlation studies revealed that weather parameters viz., rainfall, morning RH and maximum temperature showed significant correlation with aphids, jassid population was significant correlation with maximum temperature and wind velocity, thrips population was showed significant correlation with morning RH, minimum temperature and evening RH, whitefly as well as H. armigera population was showed significant correlation with minimum temperature, morning and evening RH and rosette flowers due to P. gossypiella was showed significant correlation with maximum temperature.