Effect of weather parameters on population dynamics of adults of Helicoverpa armigera and Spodoptera litura on bell pepper (Capsicum annuum L.)

In a 2-year trial early detection of Helicoverpa and Spodoptera moth catch was noticed on pheromone traps during the 10^th standard week with 2.33 and 3.52 mean moth catches, respectively in 1st year after that a progressive rise was noticed up to the 18^th standard week. The peak activity of 138.33 Helicoverpa moths per trap per week and 160.76 Spodoptera moths per trap per week was recorded on 18^th standard week. Thereafter, a sharp decline was noticed for both the pests up to the harvest of crops during the 24^th standard. Similarly, during 2nd year early detection of Helicoverpa and Spodoptera moths was too recorded during 10^th standard week with 7.54 and 6.23 mean moth catches, respectively. Which rose upto 20^th standard week with peak activity with of 143.60 Helicoverpa moths and 160.56 Spodoptera moths per trap per week in 20^th standard week. Thereafter, a sharp decline for both the pests noticed up to the harvest of crops during the 24^th standard week. The pooled data for both Helicoverpa armigera and Spodoptera litura adult populations in trap catches showed a highly significant positive correlation with temperature (maximum and minimum), highly significant negative correlation with relative humidity (morning and evening), non-significant positive correlation with sunshine hours and non-significant negative correlation with the rainfall. The overall pooled impact of weather factors on pheromone trap catches of Helicoverpa armigera and Spodoptera litura was 59.9% and 63.8% respectively.