Plant and Soil Science

Valorisation of co-products into a biopesticide: A sustainable solution for cowpea cultivation in North Cameroon

Alain Loabé Pahimi*, Hervé Leclerc Tcheumi, Jacob Tchima Massaï

alainloabe57@gmail.com

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Abstract

Co-product-based biopesticides constitute a more environmentally friendly, safe, and sustainable alternative. This study aimed to evaluate the efficacy of a biopesticide formulated from co-products (neem litter, eucalyptus litter, mango juice, rice bran) and lactobacilli on cowpea in the localities of Houla Djalingo and Badjouma. The methodology employed a completely randomised experimental design consisting of nine microplots of 25 m² each, established at two sites (Badjouma and Houla Djalingo), following the field cultivation method. The biopesticide was also formulated based on formulation methods described in the literature. It was subsequently characterised physicochemically and applied to the cowpea crop in the field on a weekly basis for three months. Its efficacy was assessed by monitoring pest dynamics over 12 weeks across biopesticide-treated plots (PTB), chemical pesticide-treated plots (PTC), and untreated control plots (PTT). Finally, seed yield and biomass (fresh and dry) were determined. The study yielded results revealing a notable reduction in pest pressure in the PTB plots. These plots recorded the highest seed weights and yields (8.6 ± 0.36 kg and 3,253 kg/ha at Houla Djalingo; 9.63 ± 0.14 kg and 3,646 kg/ha at Badjouma) and were the least affected by pest attacks compared to the PTC and PTT plots. The findings of this study can be used by farmers, agricultural extension services, and agrochemical industries to develop and disseminate a biological alternative to chemical pesticides, as well as by researchers and policymakers to support research programmes and regulatory frameworks promoting more sustainable agriculture

Keywords

agriculture; formulation; efficacy; pests; treated plots

Suggested citation
Loabé Pahimi, A., Tcheumi, H.L., & Massaï, J.T. (2026). Valorisation of co-products into a biopesticide: A sustainable solution for cowpea cultivation in North Cameroon. Plant and Soil Science, 17(3), 99-114. https://doi.org/10.31548/plant3.2026.99
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