Tropical vegetables and spices have an important contribution to make to sustainable agricultural development in Nigeria. A high proportion of these plants are cultivated, mainly in mixtures under rainfed conditions, and they are significant assets for farmers and society as a whole. They are conserved for use by people as food, medicines, fuel, fodder and building and industrial materials, contributing to the ecophysiology and biodiversity of mixed systems. But, despite these valuable attributes, current levels of productivity are well below those necessary to help create a strong, healthy Nigerian economy, and there is limited research work on their production in mixed systems. Improvements in their productivity will depend on increased efficiency in the conservation and use of these plants, targeting the smallholders, wider use of appropriate improved technologies at farm level, and greater attention to their ecophysiological values. Agricultural research aimed at these specific areas is essential for sustainable agricultural development in the country. Implications for future research in plant breeding and agronomy are highlighted.
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