Opportunities for promoting orange-fleshed sweetpotato as a mechanism for combat vitamin-a deficiency in Sub-Saharan Africa

Abstract

Sweetpotato (Ipomea batatas) is one of the most important staple crops in densely populated parts of eastern Africa and is quickly becoming an important supplementary staple in the southern part of the continent. Sweetpotato is vital to small-scale farmers with limited land, labour and capital. One of its greatest values is its ability to be harvested piecemeal for home consumption or income generation. Presently, the predominant sweetpotato cultivars in eastern and southern Africa are white-fleshed varieties that contain negligible amounts of beta-carotene, a micronutrient that the body uses to produce Vitamin A. Orange-fleshed sweetpotato (OFSP) varieties are believed to represent the least expensive, year-round source of dietary vitamin A available to poor families in the region. Studies have confirmed that African mothers can readily accept orange-fleshed varieties, thus dispelling the notion that African tastes preclude the use of all but white-fleshed cultivars. Recent estimates based on geo-referenced data show the magnitude of the potential impact of replacing white-fleshed varieties with high dry matter orange-fleshed cultivars in six East and Central African countries. Overall, over 50 million children under the age of six stand to benefit from this effort. More precisely, ex ante analysis showed that each unit kilogramme increase in per capita production of orange-flesh sweetpotato results in 1% rise in the attainment of requirements up to about 25 kilogrammes per capita. The challenge is to maintain sweetpotato status as a food security crop, and, yet stimulate its transition into a market-oriented commodity for rural income generation. The availability of improved varieties and the distribution of high quality planting materials will provide the foundation needed to achieve this objective. There has been a steady increase in both acreage and consumption levels of OFSP. For example, orange-fleshed varieties are estimated to occupy 1-2% in the lake zone of Tanzania, 5-10% in Central Uganda, 10-15% in western Kenya and 15-20% in Southern Mozambique. Consumers are primarily concerned with taste, texture and dry-matter content, and not with colour per se. Under the VITAA (Vitamin A for Africa) umbrella, 40 partner agencies from the health, nutrition and agricultural sectors have agreed to work together to extend the impact of orange-fleshed sweetpotato in seven partner countries: Ethiopia, Mozambique, Ghana, Kenya, South Africa, Tanzania and Uganda. The goal is to alleviate vitamin A deficiency among children, and pregnant and lactating mothers. VITAA represents an opportunity for the countries to tackle one of their most pressing public health problems using an existing technology that has proven to be both effective and sustainable. Activities include: breeding and selecting varieties for high dry matter content and high beta-carotene, participatory testing of varieties for adaptation and acceptability, community-based sustainable seed multiplication and distribution, nutrition education, post-harvest processing for market and for home consumption, promotion through social marketing, and monitoring of impact on nutrition and health. Implementation strategies concentrate on women because of their central role in the production and marketing of sweetpotato and other food crops used in the family diet.