ABSTRACT

Sweetpotato is increasingly important in sub-Saharan Africa due to its yield potential under sub-optimal growing conditions. But lack of planting material (seed) at the onset of the rains is a major constraint. This study examined smallholder strategies for sweetpotato seed conservation and multiplication, their agroclimatic determinants, and farmers’ perceived drought risk at four sites (Dilla, Chuko, Hawassa, Sodo) in Ethiopia using informant interviews, a survey of 278 households, and agroclimatic statistics. Conservation practices were dictated by farming system and agroecological conditions. The long-term mean length of dry period when multipliers must conserve seeds ranged between 103 and 131 days across sites. Seed multipliers faced high uncertainty of rainfall onset that varied from the end of February to mid-May. Estimated probabilities of moderate and severe droughts affecting seed conservation ranged from 36–75%, and 15–58%, respectively. In drier sites, age of multiplier, land-holding size, sweetpotato production experience and access to extension were positively associated with being a vine multiplier. Knowledge of indigenous conservations strategies should inform seed system intervention design.

摘要

由于在次优生长条件下的产量潜力，甘薯在撒哈拉以南非洲变得越来越重要。但在降雨开始时缺乏种植材料（种子）是一个主要限制因素。本研究通过知情人访谈、对 278 户家庭的调查和农业气候统计数据，研究了埃塞俄比亚四个地点（Dilla、Chuko、Hawassa、Sodo）小农户的甘薯种子保护和繁殖策略、其农业气候决定因素以及农民对干旱风险的感知。保护措施取决于农业系统和农业生态条件。倍增器必须保存种子的干旱期的长期平均长度跨站点在 103 到 131 天之间。种子倍增器面临着从 2 月底到 5 月中旬不同的降雨开始的高度不确定性。影响种子保存的中度和严重干旱的估计概率分别为 36-75% 和 15-58%。在较干燥的地区，乘数的年龄、土地拥有规模、甘薯生产经验和推广途径与成为葡萄树乘数呈正相关。土著保护战略的知识应该为种子系统干预设计提供信息。