EPAR RESEARCH BRIEF #225
Tue, 10/15/2013
AUTHORS: Travis Reynolds, Nick Papanastassiou, Alexander Chew, Alison Cullen, C. Leigh Anderson, Mary Kay Gugerty
ABSTRACT:
After cereals, root and tuber crops – including sweet potato and yam (in addition to cassava and aroids), are the second most cultivated crops in tropical countries. This literature review examines the environmental constraints to, and impacts of, sweet potato and yam production systems in Sub-Saharan Africa (SSA) and South Asia (SA). The review highlights crop-environment interactions at three stages of the sweet potato/yam value chain: pre-production (e.g., land clearing), production (e.g., soil, water, and input use), and post-production (e.g., waste disposal, crop storage and transport). We find that sweet potato and yam face similar environmental stressors. In particular, because sweet potato and yam are vegetatively propagated, the most significant (and avoidable) environmental constraints to crop yields include disease and pest infection transmitted through the use of contaminated planting materials. Published estimates suggest yield gains in the range of 30–60% can be obtained through using healthy planting material. Moreover, reducing pest damage in the field can greatly increase the storage life of root and tuber crops after harvest – currently losses from rot and desiccation can claim up to 100% of stored sweet potato and yam on smallholder farms.
This review is one in a series that examines crop-environment interactions drawing on both the academic literature and the field expertise of crop scientists. Other briefs in this series include:
- Agriculture & the Environment: Overview (EPAR Technical Report #254)
- Agriculture & the Environment: Cassava Systems (EPAR Research Brief #228)
- Agriculture & the Environment: Maize Systems (EPAR Research Brief #215)
- Agriculture & the Environment: Rice Systems (EPAR Research Brief #208)
- Agriculture & the Environment: Sorghum & Millet Systems (EPAR Research Brief #213)
- Agriculture & the Environment: Wheat Systems (EPAR Research Brief #212)
TYPE OF RESEARCH: Literature Review
RESEARCH TOPIC CATEGORY: Sustainable Agriculture & Rural Livelihoods; Agricultural Productivity, Yield, & Constraints; Environment & Climate Change
GEOGRAPHIC FOCUS: South Asia Region and Selected Countries; Sub-Saharan Africa
Downloadable Documents
Full Brief