Abstract
<title>Abstract</title> <p> A field study was conducted during the Rabi seasons of 2020-21 and 2021-22 at the Vegetable Research Centre, G.B. Pant University of Agriculture and Technology, Pantnagar (Uttarakhand), to evaluate the effectiveness of different Integrated Pest Management (IPM) modules against onion thrips, <italic>Thrips tabaci</italic> Lindeman, and their impact on primary natural enemies, particularly spiders and coccinellids, in the onion ( <italic>Allium cepa</italic> L.) crop. The experiment was arranged in a randomized block design with five treatments: Farmers’ Practice Module (FPM), Bio-intensive Module, Chemi-intensive Module, Adaptable IPM Module, and an untreated control, each replicated four times. Over both years, the Chemi-intensive module significantly reduced <italic>T. tabaci</italic> populations, recording the lowest average number of thrips per plant (10.86), followed by the Adaptable IPM (12.17), Farmers’ Practice (15.13), and Bio-intensive (21.83) modules. The untreated control consistently showed the highest thrips population (60.38 per plant). Conversely, natural enemy counts exhibited an opposite trend. The Bio-intensive module and untreated plots supported significantly higher populations of spiders and coccinellids, indicating their relative safety for beneficial arthropods. In contrast, the Chemi-intensive module had the most negative impact on predator populations. These findings suggest that while the Chemi-intensive module offers the most effective thrips control, the Adaptable IPM module provides a more balanced approach by achieving moderate pest suppression with minimal harm to natural enemies. The study emphasizes the importance of adopting environmentally safer pest management practices in onion cultivation to promote sustainable pest control. </p>