Field evaluation of plant-based oils against major sucking pests of chili

Abstract: Chilli (Capsicum annuum L.) is one of the most important spice crops globally, renowned for its pungency, flavor, and nutritional  value. This comprehensive study investigated the potential of botanical oils as sustainable alternatives for pest management in chili cultivation. A field experiment was conducted during the 2024 Rabi season at Hajee Mohammad Danesh Science and Technology University, Dinajpur, Bangladesh, employing a Randomized Complete Block Design with three replications. The study evaluated four botanical oils (neem, karanja, mahogany, and castor at 3% concentration) against the standard synthetic insecticide imidacloprid (0.2%). Results demonstrated that while imidacloprid provided the highest pest reduction (72.34% for aphids and 68.43% for thrips) and maximum yield (4.20 tons/ha, representing a 40% increase over control), botanical oils showed promising efficacy. Neem oil  emerged as the most effective botanical treatment, achieving 62.55% aphid reduction and 52.23% thrips reduction, with a yield of  3.90 tons/ha (30% increase over control). Karanja oil followed with 45.32% aphid and 44.42% thrips reduction. Economic analysis revealed competitive benefit-cost ratios for neem (3.70) and karanja oils (3.63), demonstrating their economic viability. These findings  highlight that neem and karanja oils can serve as effective, eco-friendly components of integrated pest management in chili cultivation.  They offer substantial pest control, yield improvement, and economic returns while addressing critical concerns about environmental  sustainability, pesticide resistance, and food safety. The study provides valuable insights for developing sustainable pest management strategies in chili production systems, particularly for smallholder farmers in tropical and subtropical regions. 

Keywords: Chilli, plant based pesticides, sucking pests, Scirtothrips dorsalis, Aphis gossypii,