BIO-RATIONAL MANAGEMENT APPROACHES OF MAJOR INSECT PESTS ATTACKING YARDLONG BEAN

ABSTRACT: Yardlong bean (Vigna unguiculata subsp. sesquipedalis (L.) Walp.) is an important leguminous vegetable crop in Bangladesh, and its productivity is severely constrained by major insect pests, including aphids, jassids, whiteflies, and the legume pod borer (Maruca testulalis). Excessive reliance on synthetic insecticides has resulted in resistance development and ecological disruption, highlighting the need for safer alternatives. The experiment was conducted at Gazipur Agricultural University (GAU), Gazipur using a randomized complete block design with eight treatments and three replications. The treatments included Biotrin 0.5 AS (Matrine) @ 1ml/L of water, Bio-Clean 5 SL (De- limonin) @ 1ml/L of water, Biomax M 1.2 EC (Abamectine) 1ml/L of water, mahogany Oil @ 5ml/L of water, Bio-Action 1.5 SL (Matrine) @ 1ml/L of water, Spinomax 44.3 SC (Spinosad) 1ml/L of water, neem oil @ 5ml/L of water, and untreated control. Results showed that Biomax 1.2 EC, Spinomax 44.3 SC, neem oil, and mahogany oil significantly reduced populations of aphids, jassids, whiteflies, and pod borer larvae compared with the untreated control. Spinomax 44.3 SC consistently resulted in the lowest pod infestation (9.5±0.5%) and pod borer larval density (10.3±0.4). Among all treatments, Spinomax 44.3 SC and Biomax 1.2 EC produced the highest yield (20.2±0.8 and 18.6±1.4, respectively) and marginal benefit-cost ratio (3.97 and 3.43, respectively). Botanical treatments exhibited comparatively lower adverse effects on beneficial arthropods. The findings suggest that selected bio-rational insecticides, particularly Spinomax 44.3 SC and Biomax 1.2 EC, can be effectively integrated into sustainable pest management programs for yardlong bean cultivation. 

Keywords: Maruca testulalis, Aphid, Jassid, Whitefly, IPM, Eco-friendly pest management.