International Journal of Life Science and Agriculture Research

Background: The sweetpotato weevil and sweetpotato virus disease (SPVD) are major biotic constraints that completely devastate sweetpotato fields and cause 50 – 100 % yield losses. Management includes cultural practices, tolerant varieties, chemical pesticides and integrated management strategies. Botanicals are gaining popularity in Integrated Pest and Disease Management strategies. Their insecticidal and fungicidal activities, biodegradability and safety increase their probability as alternatives to chemical pesticides. Urtica spp. are known for their insecticidal properties, but their efficacy in the management of the sweetpotato weevil and SPVD has not been documented. 

Objective: A field trial was conducted to assess the efficacy of Urtica spp. (Adamfo Pa) against sweetpotato pests and diseases in the forest and savannah transition agroecological zones of Ghana in 2025. 

Method: A Split-plot design with three replications was used. Three different rates of the extract, reference fungicide (Mancozeb WP) and biopesticide (Bypel), plus a control, were tested on Cylas sp. and SPVD susceptible sweetpotato variety. 

Results: No disease incidence was recorded. The test product at the application rate of 500 ml/100 L of water per week was effective in reducing pest infestation and damage on the leaves and storage roots. It was also found to be efficacious in minimising sweetpotato storage root damage and increasing yield. 

Conclusion: The study confirms that Urtica sp. extracts exhibit insecticidal and fungicidal properties that act as insect repellents or growth inhibitors. It is certified for use on carrots, beans, potatoes and strawberries, and recently extended to sweetpotatoes due to the outcome of this study.

Biopesticide, Cylas sp, Food security, Sweetpotato, Urtica spp.

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