EXPLORING PLANT-BASED PESTICIDES AS VIABLE ALTERNATIVES FOR CONVENTIONAL AGROCHEMICALS IN MAIZE FARMING

Abstract

Plant-derived botanical formulations were evaluated as sustainable alternatives to synthetic agrochemicals for maize (Zea mays L.) pest and disease management. Six botanicals—neem (Azadirachta indica), basil (Ocimum basilicum), thyme (Thymus vulgaris), sage (Salvia officinalis), celery (Apium graveolens), and Tagetes minuta—were assessed through laboratory bioassays, greenhouse trials, and simulated storage studies. Insecticidal assays against the maize weevil (Sitophilus zeamais) demonstrated dose-dependent efficacy, with T. minuta and neem achieving the highest mortalities of 88% and 85%, respectively, at 1.0% concentration. Antifungal tests against Fusarium spp. revealed that thyme and sage essential oils inhibited mycelial growth by 72% and 68%, respectively. Seed germination and seedling vigor remained robust across all treatments (>90% germination; vigor indices 2,150–2,300), indicating negligible phytotoxicity. Residue analyses via GC-MS showed that active compounds degraded by over 50% within 30 days and fell below 0.30 mg/kg by day 60, aligning with food safety thresholds. Greenhouse evaluations confirmed significantly reduced disease incidence (15–40% vs. 60% in controls) and lower severity indices (0.9–2.8 vs. 3.8). These findings underscore the dual benefits of botanical pesticides—effective pest and pathogen control coupled with rapid biodegradation—supporting their integration into integrated pest management (IPM) frameworks. Field-scale validation, formulation optimization (e.g., nanoencapsulation), and economic analyses are recommended to facilitate adoption. This study provides a comprehensive, data-driven foundation for the development and deployment of plant-based pesticides in maize production, offering a pathway toward residue-free, environmentally responsible agriculture