Vol. 12, Special Issue 11 (2023)

Author(s):
KV Deshmukh, CS Patil, AR Walunj, RS Wagh, VP Chimote and NK Bhute

Abstract:
The objective of this current study was to document the fluctuation in population of lepidopteran pests in Bt cotton fields and to assess the influence of weather parameters on their population dynamics. The data revealed that during Kharif-2020 and 2021, the presence of Helicoverpa armigera larvae on Bt cotton displayed varying patterns, ranging from 0.16 to 1.08 larvae per plant in 2020 and 0.20 to 1.14 larvae in 2021. The highest incidence occurred in the 37^th MW of both years, reaching 1.04 and 1.14 larvae per plant respectively. Similarly, Earias vittella population followed a comparable trend, emerging in the 31^st MW and persisting until the 41^st MW, with the peak occurrence observed in the 35^th MW, recording 1.46 and 1.64 larvae per plant in 2020 and 2021 respectively. Spodoptera litura larval population in 2020 ranged from 0.38 to 2.18 per plant, with the highest incidence in the 37^th MW at 2.18 larvae per plant. During Kharif 2021, the range was 0.28 to 2.24 larvae per plant and reached its peak in the 37^th MW at 2.24 larvae per plant.