Population dynamics and weather associations of major sucking insect pests on chilli (Capsicum annuum L.) under open-field conditions
Year: 2026
Type: article
Abstract: Background: Sucking insect pest are one of the major biological challenges to chilli (Capsicum annuum L.) productivity, and their seasonal incidence is strongly affected by prevalent weather conditions. Assessment of pest and weather associate is vital for development of weather-based pest forecasting and integrated pest management (IPM) approaches. This study examined the seasonal population dynamics of major sucking insect pests and their associations with abiotic factors under open field conditions. Methods: The investigation was carried out during the Rabi season at the Vegetable Research Centre, G.B. Pant University of Agriculture and Technology, Pantnagar, Uttarakhand, India. Counts on aphids (Aphis gossypii), thrips (Scirtothrips dorsalis), and whiteflies (Bemisia tabaci) were taken at fortnight intervals from transplanting to harvest of the crop. The ANOVA (analysis of variance) was employed to analyse population dynamics along with Pearson's correlation and simple linear regression analyses to evaluate the associations between pest populations and seven weather parameters. Results: All three sucking insect pests displayed varied seasonal fluctuations, with populations increasing progressively from the early crop stage, attaining a peak during the 2nd Standard Meteorological Week, and decreasing thereafter. Aphid incidence displayed significant negative correlations with maximum and minimum temperatures with a significant positive correlation with morning relative humidity. Thrips incidence exhibited a significant positive association with morning relative humidity, whereas maximum and minimum temperatures displayed marginally significant negative correlations. In contrast, whitefly incidence exhibited weak, non-significant associations with all measured weather parameters. Further, regression analysis reinforced maximum temperature as the strongest predictor of aphid incidence (R2=0.521, P=0.028), while morning relative humidity was found as the primary predictor of variation in thrips incidence (R²=0.472, P=0.041). None of the individual weather parameters significantly correlated with whitefly incidence. Conclusion: The results suggest that temperature and relative humidity are consistent predictors of aphid and thrips incidence and may aid for developing weather-based pest forecasting models for chilli under open field conditions. Nonetheless, forecasting whitefly incidence may require the integration of additional crop and biotic factors. Further investigations are required to validate these associations and improve integrated pest management strategies.
Language: English
Subfield: Insect Science
Domain: Life Sciences
SDG: Zero hunger
Open Access status: diamond
OpenAlex ID: W7203573248