Phytochemical Screening and the Efficacy of Leaf Extract and Powder of Ageratum conyzoides against Callosobrochus maculatus Fabricius (Coleoptera: Chrysomelidae) on Stored Cowpea Seeds
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275-290
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10.58578/ajstea.v4i3.9126
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Authors:
Obembe Olusola Michael1*, Kayode Emmanuel Olamide2, Adegbola Mary Adeola3 
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Abstract
Cowpea weevil, Callosobruchus maculatus, is a major pest of stored grains worldwide and causes substantial postharvest losses in cowpea storage systems. This study evaluated the insecticidal efficacy of leaf powder and ethanol leaf extract of Ageratum conyzoides against C. maculatus based on adult mortality, oviposition, adult emergence, long-term storage protection, seed viability, and phytochemical composition. Fresh leaves of A. conyzoides were air-dried, ground into fine powder, and partially extracted in ethanol at 60 °C for 30 min. The extract was filtered, concentrated using a rotary evaporator, and prepared at concentrations of 2%, 4%, 6%, and 8% (v/w), while leaf powder was tested at dosages of 1, 2, 3, and 4 g (w/w). Phytochemical screening was conducted using standard procedures. The findings show that adult mortality increased with increasing extract concentration, powder dosage, and exposure time. Cowpea seeds treated with A. conyzoides powder at 8 g (w/w) recorded 92.25% mortality within 96 h, whereas 100% mortality was achieved with 8.0% (v/w) ethanol extract within the same exposure period. No oviposition occurred on seeds treated with 8.0% (v/w) extract, and no adult emergence was observed in seeds treated with 4 g (w/w) powder. Extract concentrations of 4%, 6%, and 8% (v/w) completely prevented seed damage during three months of storage, while germination tests after seven days showed 100% germinability in all treated seeds. Phytochemical analysis revealed the presence of alkaloids, glycosides, saponins, anthraquinones, tannins, terpenes, and flavonoids. The study concludes that A. conyzoides leaf powder and ethanol leaf extract are effective botanical treatments for controlling C. maculatus without compromising seed viability. These findings contribute to stored-grain pest management by supporting the use of plant-based insecticides as environmentally safer and potentially cost-effective alternatives to synthetic insecticides.
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References
Adedire, C. O., & Ajayi, T. S. (2003). Potential of sand and plant powders in the control of Callosobruchus maculatus (F.) infestation in stored cowpea seeds. Journal of Plant Diseases and Protection, 110(6), 602–610.
Adedire, C. O., Obembe, O. M., Akinkurolere, R. O., & Oduleye, S. O. (2011). Response of Callosobruchus maculatus (Coleoptera: Chrysomelidae: Bruchinae) to extracts of cashew kernels. Journal of Plant Diseases and Protection, 118, 75–79. https://doi.org/10.1007/BF03356385
Adesina, J. M. (2013). Insecticidal potential of Momordica charantia (L.) leaves powder against maize weevil, Sitophilus zeamais (Mots) (Coleoptera: Curculionidae) infestation. International Journal of Biosciences, 3, 28–38.
Arthur, F. H., Starkus, L. A., & Phillips, T. W. (2018). Physical and botanical insecticides for stored-product protection. Journal of Stored Products Research, 77, 1–10.
Asawalam, E. F., Emosairue, S. O., Ekeleme, F., & Wokocha, R. C. (2007). Insecticidal effects of powdered parts of eight Nigerian plant species against maize weevil, Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae). Electronic Journal of Environmental, Agricultural and Food Chemistry, 6(11), 2526–2533.
Benelli, G., Pavela, R., Canale, A., & Mehlhorn, H. (2016). Tick repellents and acaricides of botanical origin: A green roadmap to control tick-borne diseases? Parasitology Research, 115(7), 2545–2560. https://doi.org/10.1007/s00436-016-5095-1
Bryant, T., & Reay-Jones, F. P. F. (2020, May). Integrated pest management: Concepts and strategies. Land-Grant Press by Clemson Extension. https://lgpress.clemson.edu/publication/integrated-pest-management-concepts-and-strategies/
Caswell, G. H. (1984). Damage to stored cowpea in the northern part of Nigeria. Samaru Journal of Agricultural Research, 2, 11–19.
de Mendonça, F. A. C., da Silva, K. F. S., dos Santos, K. K., Ribeiro Júnior, K. A. L., & Sant’Ana, A. E. G. (2005). Activities of some Brazilian plants against larvae of the mosquito Aedes aegypti. Fitoterapia, 76(7–8), 629–636. https://doi.org/10.1016/j.fitote.2005.06.013
Fatope, M. O., Nuhu, A. M., Mann, A., & Takeda, Y. (1995). Cowpea weevil bioassay: A simple prescreen for plants with grain protectant effects. International Journal of Pest Management, 41(2), 84–86. https://doi.org/10.1080/09670879509371928
Harborne, J. B. (1998). Phytochemical methods: A guide to modern techniques of plant analysis (3rd ed.). Chapman & Hall.
Harborne, J. B. (2010). Phytochemical methods: A guide to modern techniques of plant analysis (3rd ed.). Springer India.
Ileke, K. D. (2014). Antinutritional factors determining the susceptibility of cowpea to cowpea bruchid, Callosobruchus maculatus (Fab.) (Coleoptera: Chrysomelidae) infestation. Bioscience Methods, 5(2), 1–8.
Ileke, K. D., & Bulus, D. S. (2019). Response of Callosobruchus maculatus to powders and extracts of botanical insecticides. Journal of Plant Diseases and Protection, 126, 123–131.
Ileke, K. D., & Oni, M. O. (2011). Toxicity of some plant powders to cowpea bruchid, Callosobruchus maculatus (F.) (Coleoptera: Bruchidae). Journal of Agricultural Technology, 7(4), 1119–1128.
Ileke, K. D., Idoko, J. E., Ojo, D. O., & Adesina, B. C. (2020). Evaluation of botanical powders and extracts from Nigerian plants as protectants of maize grains against maize weevil, Sitophilus zeamais (Motschulsky) [Coleoptera: Curculionidae]. Biocatalysis and Agricultural Biotechnology, 27, Article 101702. https://doi.org/10.1016/j.bcab.2020.101702
Isman, M. B. (2006). Botanical insecticides, deterrents, and repellents in modern agriculture and an increasingly regulated world. Annual Review of Entomology, 51, 45–66. https://doi.org/10.1146/annurev.ento.51.110104.151146
Isman, M. B. (2020). Botanical insecticides in the twenty-first century: Fulfilling their promise? Annual Review of Entomology, 65, 233–249. https://doi.org/10.1146/annurev-ento-011019-025010
Isman, M. B., & Grieneisen, M. L. (2014). Botanical insecticide research: Many publications, limited useful data. Trends in Plant Science, 19(3), 140–145. https://doi.org/10.1016/j.tplants.2013.11.005
Kayode, J., & Obembe, O. M. (2012). Assessment of the insecticidal potentials of the aqueous extracts of some tropical trees as protectant of cowpea seed from Callosobruchus maculatus infestation. Bio-Science Research Bulletin, 28(1), 39–47.
Lale, N. E. S., & Abdulrahman, H. T. (1999). Evaluation of neem (Azadirachta indica A. Juss.) seed oil obtained by different methods and neem powder for the management of Callosobruchus maculatus (F.) (Coleoptera: Bruchidae) in stored cowpea. Journal of Stored Products Research, 35(2), 135–143. https://doi.org/10.1016/S0022-474X(98)00039-3
Obembe, O. M. (2021). Effects of processing methods on proximate composition of groundnut seed (Arachis hypogea L.) during storage period. FUTA Journal of Life Sciences, 1(1), 53–60.
Obembe, O. M., Adebayo, R. A., & Ajayi, O. E. (2021). Evaluation of botanical insecticides for the control of Callosobruchus maculatus on stored cowpea seeds. African Journal of Agricultural Research, 17(4), 512–520.
Obembe, O. M., Philip-Attah, M. T., & Adegbola, M. A. (2025). Entomocidal activity of Alstonia boonei de Wild oil extracts against cowpea beetle, Callosobruchus maculatus Fabricius (Coleoptera: Bruchidae) infesting stored cowpea seeds. Journal of Bioscience and Biotechnology Discovery, 10(4), 79–85. https://doi.org/10.31248/JBBD2025.238
Ofuya, T. I. (2001). Biology, ecology and control of insect pests of stored grains. In T. I. Ofuya & N. E. S. Lale (Eds.), Pests of stored cereals and pulses in Nigeria (pp. 59–94). Dave Collins Publications.
Ofuya, T. I. (1986). Use of wood ash, dry chilli pepper fruits and onion scale leaves for reducing Callosobruchus maculatus (Fabricius) damage in cowpea seeds during storage. Journal of Agricultural Science, 107(2), 467–468. https://doi.org/10.1017/S0021859600087281
Ofuya, T. I., & Bamigbola, K. A. (1991). Damage potential of Callosobruchus maculatus (F.) on cowpea seeds. Journal of Stored Products Research, 27(2), 89–94.
Pavela, R., & Benelli, G. (2016). Essential oils as ecofriendly biopesticides? Challenges and constraints. Trends in Plant Science, 21(12), 1000–1007. https://doi.org/10.1016/j.tplants.2016.10.005
Raghuram, C. P. (2015). Insecticidal activity of botanical pesticides on Callosobruchus chinensis L. (Coleoptera: Bruchidae) on the stored green gram, Vigna radiata (L.). International Journal of Agricultural Science Research, 4, 13–20.
Singh, B. B., Ehlers, J. D., Sharma, B., & Freire Filho, F. R. (2002). Recent progress in cowpea breeding. In C. A. Fatokun, S. A. Tarawali, B. B. Singh, P. M. Kormawa, & M. Tamò (Eds.), Challenges and opportunities for enhancing sustainable cowpea production (pp. 22–40). International Institute of Tropical Agriculture.
Ukeh, D. A., Umoetok, S. B. A., & Umoru, P. A. (2021). Botanicals as alternatives to synthetic insecticides in stored-product pest management. Environmental Sustainability, 4, 245–256.
Yang, Z., Zhao, B., Zhu, L., Fang, J., & Xia, L. (2006). Inhibitory effects of alkaloids from Sophora alopecuroids on feeding, development and reproduction of Clostera anastomosis. Frontiers of Forestry in China, 1(2), 190–195. https://doi.org/10.1007/s11461-006-0016-6