Vol. 10, Special Issue 11 (2021)

Author(s):
Shalendra Pratap Singh, Rama Kant Dwivedi and Kaushal Kishor

Abstract:
A field experiment was conducted at Chandra Shekhar Azad University of agriculture and technology Kanpur (U.P) on tomato crop to study the population of Halicoverpa armigera and their relation with weather parameters during rabi season 2018-19 and 2019-20. Initial incidence of the pest was observed on 30.12.2019, in 52^th standard week i.e., with a mean number of fruit infestation of 0.05. Thereafter the population of Halicoverpa armigera increase with increase in temperature during winter season. The fruit damage reached to peak by March 26, 2019 when the temperature increases and favorable for insect growth and development with mean larval population of 2.88 during 14^th standard week. The results indicated positive significant correlation association between the maximum temperature (r= 0.503*), (r= 0.402*) and minimum temperature (r = 0.613**), (r= -0.419*) with the larval population prevailing during this period and positive significant association with morning or maximum relative humidity (r = 0.664**), (r=-0.692**) and negative non significant association with evening or minimum relative humidity (r = -0.008**), (r=-0.004**) with the larval population. The correlation relationship was negative and non-significant with rain fall and wind speed i.e. (r = - 0.164**), (r = - 0.180**) and (0.792**), (r = - 0.168**) respectively. The correlation between larval population and sun shine hrs was positively significant i.e. (r = 0.491*), (r = 0.238*).