ISSN 2360-7971
Abstract
This study evaluated aqueous leaf extracts of Plumeria rubra, Tephrosia candida and Anogeissus leiocarpus for toxicity and repellency against the subterranean termite Macrotermes subhyalinus in laboratory bioassays. Crude extracts were prepared and applied at 10, 20, 30 and 40% w/v to filter papers; twenty worker termites per Petri dish (three replicates) were exposed, and mortality was recorded at 24 and 48 hours. All extracts produced dose-dependent mortality; at 40% w/v, A. leiocarpus caused 75.0% mortality at 24 h, while P. rubra and T. candida produced 71.7% and 71.7%, respectively; all extracts attained 100% mortality by 48 h (the diazinon positive control achieved 100% at 24 h; distilled water had no effect). In repellency assays (30 min exposure), extracts showed 50–71% repellence at the highest dose. Phytochemical screening indicated the presence of alkaloids, flavonoids, tannins and eugenol-related compounds that likely contribute to activity. These results indicate that the tested botanicals have potential as locally available termite control agents; further work is recommended to standardise extraction, determine LC50/LT50 values, evaluate field efficacy and develop safe formulations.
Keywords: Botanical termiticides, Macrotermes subhyalinus, Pest management, Phytochemical screening