Population dynamics of Helicoverpa armigera with pheromone traps in relation to weather parameters in pigeonpea

Abstract

The field experiments on population dynamics of Helicoverpa armigera with pheromone traps information in pigeonpea at the International Crops Research Institute for Semi-Arid Tropics (ICRISAT) Hyderabad, during 2016-2017 and 2017-2018. During 2016-17 results revealed that the adult moth population of H.
armigera was first time appearing in the field during 22th std. week (June 1st to 3rd) with (1.20 moths/5trap/ week). H. armigera moths population increased on 34 and 35 SMW (13 to 14 moths/5trap/week) respectively, it was associated with maximum and minimum temperature were ranged from 29.3oC to 31.9oC and 23.4oC to 24.1oC respectively along with 85% morning relative humidity 57.7 to 64.9% evening relative humidity. The population abruptly decreased to 2.91 during 36 std. week there after moth population remained more or less static throughout the cropping season. During 2017-18 the peak activity of H. armigera adult moth population appeared on 35 SMW (3.80 moths/5trap/week), and was associated with maximum and minimum temperature were ranging from 29.3oC to 21.9oC respectively along with 91.4% and 71.6% morning and evening relative humidity respectively. A non-significant correlation existed between adult moth and the maximum and minimum temperature with (r =-0.214) and r=0.21 respectively. While morning relative humidity, evening relative humidity and rainfall showed significant positive correlation (r = 0.263, 0.363 and 0.532 respectively) with H. armigera moth populations.