Vol. 9, Special Issue 5, Part D (2025)

A field study was conducted during the 2023-24 Kharif-Rabi season at Sam Higginbottom University of Agriculture, Technology and Science, Prayagraj, to investigate the population dynamics of Thrips parvispinus in chilli crops and its correlation with weather parameters. Infestation began in mid-August (33^rd SMW) with 0.26 thrips per flower, coinciding with the onset of flowering, and peaked in early January (1^st SMW) at 14.67 thrips per flower. The highest populations were observed under cooler temperatures (mid to low 20s °C), low rainfall, and elevated morning relative humidity. In contrast, lower infestation levels (<1.00 thrips/flower) occurred during periods of high maximum temperatures (mid to upper 30s °C) and minimal rainfall. Correlation analysis revealed significant negative relationships between thrips population and maximum temperature (r = -0.931**), minimum temperature (r = -0.904**), and sunshine hours (r = -0.432**). Other parameters, such as rainfall and relative humidity, showed non-significant correlations. Multiple linear regression indicated that the combined weather variables explained 93.00% (R² = 0.930) of the variation in thrips population. These results highlight the critical role of climatic factors in influencing T. parvispinus population dynamics, providing a foundation for developing weather-based integrated pest management strategies to improve chilli crop productivity.