Let’s Eat Orange! Unleashing the Potential of Biofortified Sweetpotato in Africa
This post is written by Jan W. Low, International Potato Center.
I firmly believe that there are no magic bullets, but there can be breakthrough products or methods that help us combat malnutrition. Vitamin A rich, orange-fleshed sweetpotato (OFSP) in Africa is such a product — but it required undertaking a campaign to create demand, so that a switch would be made from the preferred, dominant white-fleshed sweetpotatoes to the orange variety. To improve the vitamin A status of young children, community-based nutrition promoters operated alongside agricultural extensionists to ensure caregivers improved feeding and hygiene practices. Understanding the five distinct phases of the innovation process over the past 25 years revealed the time it truly takes to overcome technical and organizational barriers. Moreover, persistence in the mission by committed scientists was key not only in raising the funds for the evidence-building research, but also to influence the institutions and policies to create an enabling environment and to respond to emerging opportunities.
The major scaling phase in 15 African countries occurred under the umbrella of the multipartner, multidonor (including USAID) institutional innovation known as the Sweetpotato for Profit and Health Initiative (SPHI), led by the International Potato Center (CIP) and the Forum for Agricultural Research in Africa (FARA). From 2010-2019, 6.3 million households received improved varieties of sweetpotato. The foundation of this work was a major investment in breeding in Africa for Africa, funded by the Bill & Melinda Gates Foundation and the Alliance for a Green Revolution in Africa (AGRA), enabling 13 African countries to breed sweetpotato, instead of just two countries. As CIP sweetpotato breeder Maria Andrade notes, "We learned the hard way that just bringing in best bets from outside Africa was not enough. The drought tolerance we breed for in Mozambique is a difficult trait, so conventional crossing of orange-fleshed types with local landraces that survived a long drought was essential to develop truly adapted varieties." Combined with a new method — the accelerated breeding scheme — breeders in Mozambique, Malawi and South Africa have released 28 drought-tolerant OFSP varieties since 2010.
Like humans, plants suffer from viruses and sweetpotato is no exception. The insects that transmit sweetpotato viruses survive year-round in bimodal rainfall areas in the belt that runs along either side of the equator. As certain viruses such as the sweetpotato virus disease (SPVD) complex accumulate, the productivity of the plant declines. Cuttings from vines are the major source of sweetpotato planting material in the tropics, so having virus-free planting material is a key goal of those managing "seed systems." Another way to combat viruses is to breed for virus resistance, a major objective among breeders in East and Central Africa. Applying the principles of exploiting hybrid vigor in sweetpotato breeding enabled significant breeding progress for virus resistance during the past decade.
Concurrent with breeding efforts was the development, validation and scaling of delivery systems to ensure that desired targets of improving food security, nutritional status and/or incomes were met. Given that most farmers retain their own planting material or get it from neighbors, developing sustainable mechanisms for seed delivery and assuring the quality of that seed in different contexts has been one of the most challenging components. The existence of a strong market for roots or an extensive period of drought are factors that drive willingness to pay for sweetpotato planting material.
One of the major problems faced initially was the poor image of sweetpotato among policy makers. It is considered a poor woman’s crop in many countries, just for food security. In East and southern Africa, it is known as the crop that is there when the maize fails; in Rwanda it is called "local defense." Moreover, no one wakes up in the morning saying, "I feel vitamin A deficient today." Hence, there was a need to raise awareness of the critical role that vitamin A plays in assuring a strong immune system and good eyesight; raise the need to consider women’s crops in prioritization exercises; and to promote the commercialization of OFSP — both as fresh roots and as an ingredient for diversified processed products, like bread, biscuits and juices. In rural areas, emphasis was placed on how to add OFSP roots and leaves into traditional dishes and to make nutritionally balanced porridges for young children. As urban consumers often opt for convenience, the focus was on developing value chains to produce processed sweetpotato products using OFSP purée (steamed and mashed roots), creating new markets for farmers. In CIP-led projects, efforts were undertaken to ensure strong female participation in commercialization efforts.
The unique nature of the advocacy work undertaken, particularly by HarvestPlus — a program focused on biofortified staple crops — CIP and others, resulted in the widespread integration of biofortified crops as part of nutrition and agricultural policies in 24 countries in sub-Saharan Africa and several regional bodies, such as the African Union. The orange color of OFSP varieties has proved to be a marketing tool and teams have had fun decorating market stalls, vehicles, attire and posters, developing slogans and arranging orange-themed food fairs and other events to get the message out about how the orange and green colors of OFSP roots and leaves, as well as many other vegetables and fruits, are indicative of the presence of micronutrients that are good for your health.
Use of OFSP is no doubt going to expand in Africa and elsewhere in the tropics in the future. The fact that it is a rich source of vitamin A and a good source of many other micronutrients and energy, has short duration varieties available, can be grown from sea level to 2,400 meters and is more water efficient than grains means that it is truly a crop that will help us build forward better as we emerge from the COVID-19 pandemic.