Influence of weather on the moth catches of Helicoverpa armigera at various cotton-based agro-ecological sites

Pheromones are innate products, exploited for direct population manipulation in the trapping of precise pest density. They demonstrate feasibility and efficiency against Helicopverpa armigera at five different cotton-based agro-ecological sites: river site, vegetable farm, orchard, clean cultivation site, and forest. The data were recorded at 15–20 day intervals from 8 September 2004 to 1 December 2006. The Number of moths caught during the study period demonstrated that the vegetable farm showed the maximum population of moths per trap (0.54), followed by the orchard (0.29), forest (0.19), river (0.15), and clean cultivation site (0.12). During 2004, rainfall (in the orchard and clean cultivation site) and relative humidity (in the clean cultivation site) showed positive and significant correlation with the number of moths caught. During 2005, temperatures played a significant and positive role in population fluctuation of the pest almost at all the selected sites; the minimum temperature was recorded at the vegetable farm and the average temperature was found at the forest site. Rainfall also showed a significant and positive correlation with trapped moths in the vegetable farm, orchard, and clean cultivation site. During 2006, relative humidity showed a significant and negative correlation with the trapped population at all the sites except the river site. Rainfall showed a negative and significant correlation with the pest at the forest site. Relative humidity was the most important aspect at 8.93% causing variation in the trapped population followed by maximum temperature (5.7%), rainfall (1.63%), average temperature (0.74%), and minimum temperature (0.56%).