Sweet Potato Weevil Damage, Production Constraints, and Variety Preferences in Western Tanzania: Farmers’ Perception

ABSTRACT

Sweet potato weevils (Cylas spp.) are among the most important constraints to sweet potato (Ipomoea batatas [L.] Lam.) production in most agro-ecological zones of Tanzania. Integration of farmers’ perception on sweet potato weevil damage, production constraints, and variety preferences is crucial in developing sweet potato varieties with farmer-preferred traits and weevil resistance. The aim of this study was to identify farmers’ perceptions on sweet potato weevil damage, production constraints, postharvest storage options, and criteria used to select and grow the best sweet potato varieties in western Tanzania. Surveys were conducted in four selected districts of western Tanzania (Nzega, Sikonge, Kigoma rural, and Kasulu) known for sweet potato production. Data were collected using a structured questionnaire, focus group discussions (FGDs), and transect walk involving 122 sweet potato farmers. Weevil damage was reported by 84% of the respondents to be the overriding constraint to sweet potato production. Sweet potato diseases and drought were the next production constraints, reported by 57% and 54% of the respondents, respectively. Farmers’ preferred agronomic traits of sweet potato included high yield (25% of respondents), drought tolerance (24%), and disease and pest resistance (21%). Farmers’ preferred sweet potato culinary traits in the study areas were high dry matter content (reported by 21% of the respondents), followed by reduced cooking time, taste and fiber content (each reported by 19% of the respondents). The above-mentioned production constraints and farmers’ preferred traits are useful selection criteria for improving sweet potato with respect to weevil resistance and enhanced storage-root yield and quality.

KEYWORDS:

• Agronomic traits
• culinary traits
• Cylas spp
• resistance breeding
• weevil-resistant varieties

Acknowledgments

The first author is grateful to the Tanzanian Ministry of Agriculture, Livestock and Fisheries through Tumbi Agricultural Research Institute (ARI-Tumbi) for providing leave of absence and research support. The district agricultural offices of the study districts are thanked for providing extension officers who assisted in this study. We are grateful to farmers of the study areas who made this participatory rural appraisal study possible.

Funding

This work was financed by the Alliance for a Green Revolution in Africa (AGRA) through the African Centre for Crop Improvement (ACCI)-PhD funding.