Vol. 12, Issue 11 (2023)

Author(s):
N Sunita Devi, KI Singh, Nilima Karam, SM Haldhar, Bireswar Sinha and Moirangthem Monalisa Devi

Abstract:
A study on the seasonal incidence of Helicoverpa armigera on tomato was studied at the Vegetable Research Farm, College of Agriculture, Central Agricultural University, Imphal during two consecutive Rabi seasons of 2020-21 and 2021-22. The study revealed that the first appearance of Helicoverpa armigera in both the years was observed from 7^th standard meteorological week i.e. 12^th-18^th February, with similar mean population of 0.13 larvae per plant. Thereafter the larval population gradually increased and attained maximum population of 2.23 and 2.15 larvae per plant on 12^th and 13^th standard meteorological week in both the years respectively. During 2020-21, the correlation studies showed that there was positive and significant association with maximum temperature. However, in 2021-22, Minimum temperature showed positive and significant correlation with larval population.