Eco-epidemiology and climate-based IPM of pink bollworm (Pectinophora gossypiella Saunders) in cotton (Gossypium hirsutum L.) in farmer fields of Warangal, Telangana

Abstract

Pink bollworm (Pectinophora gossypiella Saunders) remains a major pest in cotton (Gossypium hirsutum L.) cultivation in Warangal, India, causing considerable yield and economic losses. A three-year, multi-location study (2022-24) was conducted in farmer fields of Warangal district to assess seasonal pest dynamics, weather influence, and economic performance of Integrated Pest Management (IPM) compared with conventional Farmer Practice (FP). The IPM strategy, combining pheromone traps, cultural practices, biological agents (Trichogramma chilonis, Beauveria bassiana, neem oil), and need-based chemical sprays, consistently suppressed larval populations (7.0-7.8 larvae/50 bolls in peak month; overall 9.6-19.5) relative to FP plots (14.2-24.4 larvae/50 bolls), reduced rosette flower incidence (2.8-8.5% vs 6.1-26.9%), and minimized green boll damage (2.0-7.5% vs 15-21%). Peak PBW activity occurred in October during boll formation, followed by a rapid decline. Pearson correlation and multiple regression analyses identified rainfall as the principal inhibitory factor (r = -0.70), while temperature and sunshine hours moderately favored larval development; the regression model explained 72% of variability in IPM plots. IPM interventions increased cotton yield by 43.5-57.3% (30.5-35.0 q/ha), improved net returns (₹124,715-172,450/ha), and achieved higher benefit-cost ratios (2.72-2.90:1) than FP. Technology Index and Technology Achievement Index trends indicated enhanced adoption and efficiency of IPM practices. Overall, climate-responsive IPM effectively suppressed PBW, improved productivity and profitability, and provides a sustainable, eco-friendly strategy for cotton cultivation in Warangal, India.