Influence of agro-climatic parameters on the seasonal incidence of mirid bug (Nesidiocoris tenuis L.) in sesame

Abstract

The mirid bug Nesidiocoris tenuis poses a growing threat to sesame crops. A two-year field study was conducted during Kharif 2023 and 2024 at JNKVV, Jabalpur, to examine pest incidence and its relationship with agro-climatic variables under unsprayed conditions. The peak population densities of mirid bug during both the years coincided with the flowering and capsule development stages. Among the tested weather variables, minimum temperature consistently showed the strongest correlation with mirid bug incidence (r = 0.788 in 2023; r = 0.842 in 2024), followed by morning vapour pressure (r = 0.763 and 0.798) and evening vapour pressure (r = 0.721 and 0.758). Relative humidity evening (r = 0.819 in 2024), morning (r = 0.649 in 2023), wind speed (r = 0.684 in 2024), and evaporation (r = 0.704 in 2023) also exhibited significant positive associations with the incidence of mirid bug. Regression analysis reinforced these associations, revealing strong predictive relationships with pest dynamics across seasons. The peak incidence of mirid bug coincided with minimum temperatures of 24 to 25 °C and vapour pressure above 22 mm. These findings will aid in the development of a pest forecasting module for mirid bugs in sesame by integrating thermal and humidity cues.