CIP is a recognized global leader in the development and dissemination of biofortified, vitamin A-rich OFSP. The use of OFSP, when introduced along with nutrition education at the community level, is a proven cost‐effective strategy for providing vitamin A at high levels of bioavailability to vulnerable populations. OFSP production from 500 m2 can provide sufficient vitamin A for a family of five and is a good source of energy, a number of B vitamins, and vitamins C and K. These are vital benefits for the majority of people affected with VAD who live in rural areas where conventional VAD interventions such as supplementation and food fortification are ineffective. The strategic advantage of biofortified crops is that they sustainably build micronutrient supply into the regular, daily food production and consumption patterns without need for continuous investments in the delivery of nutrition supplements. However, biofortified crops overall lack a strong evidence base of efficacy in the field at this stage—with the notable exception of OFSP. Still, for OFSP to achieve its full nutrition impact, linkages with other biofortification efforts (e.g., providing different micronutrients, using different crops) are important, as are complementarities with nutrition supplementation and education programs. In Zambia, we are already coordinating our OFSP work with the HarvestPlus orange maize project under one joint R&D program. We are also a partner to the HarvestPlus combined OFSP and high-iron beans program in Uganda and Rwanda. In Nigeria, we are developing similar linkages with a yellow cassava program led by the International Institute of Tropical Agriculture (IITA). Working through RTB and A4NH, and also with Dryland Systems, Humidtropics, and AAS CRPs, CIP will pursue its OFSP objective in this wider context, targeting regions and farming systems where sweetpotato has a comparative advantage as a biofortified crop and, where possible, harnessing advances made by other crops in technology development and delivery systems.
Having demonstrated the efficacy of OFSP in several African countries, CIP is now responding to increasing global demand through a phased scaling-up program in SSA, Asia, and the Caribbean (Haiti). These include countries and provinces where sweetpotato is well established as a food security crop and OFSP varieties add specific nutritional benefits. In other countries, OFSP will be the first sweetpotato and its contribution to nutrition will be the main benefit. In all cases, scaling-up efforts will focus on locations where sweetpotato has an inherent agronomic advantage as a short-cycle crop that requires few inputs and can produce comparatively high yields even under marginal conditions. In SSA, sweetpotato is predominantly grown by smallholder farmers—women in particular—with yields of 4–10 MT/ha in most countries. Yet, these yields can be increased by at least 50%, even in rainfed smallholder production systems, through a combination of improved varieties, clean planting materials, and good agronomic practices. In the higher input systems in Asia, sweetpotato reaches yields of over 20 MT/ha, though here, too, smallholder productivity lags behind this potential (see Annex 1 for country-level data). Sweetpotato is thus a valuable and flexible component in a range of farming systems important to the poor.
Sweetpotato’s fit in farming systems
Sweetpotato’s role varies greatly in local farming systems across SSA and Asia, and our strategy addresses two basic scenarios. In several countries, such as in the high population areas of the African Great Lakes Region and parts of China and South Asia, sweetpotato is well established as a food security crop, though the fit in farming systems differs. In SSA, sweetpotato is often a second or third crop after maize, bananas, or cassava in mixed smallholder farming systems. In Asia it fits within rice-dominated systems as a seasonal crop or is produced on commercial scale in intensive systems. Sweetpotato enjoys high productivity per unit land area and labor even on more marginal lands (4–6 MT/ha). Its short growing cycle either allows for flexible planting and harvesting times in high rainfall regions or, in drier areas or areas prone to droughts or floods, permits quick production within a 4- to 5-month window. Farmers appreciate additional agronomic benefits from sweetpotato such as good groundcover, availability of surplus biomass from vines for animal feed, and the possibility of using planting material from own fields. On all these accounts, sweetpotato enhances the resilience of smallholder farming that is frequently affected by low yields or crop failure of other staple crops due to weather or disease (maize, cassava, and bananas have all been affected by major diseases over the past years in SSA). Sweetpotato is not a regionally or internationally traded crop, so has proven to be less affected by food price fluctuations than most of the main cereals. It continues to provide affordable food during times of high food prices.
In other areas, such as parts of Southeast Asia and Ethiopia, West Africa, and Southern Africa, sweetpotato is a relatively new crop and so is much less prevalent. Dry or high-altitude conditions limit its use. In these locations, farmers have started to adopt OFSP for its nutritional qualities and view it mainly as a supplementary crop, grown on small plots, to meet nutritional needs of children or specific market opportunities. Still, high productivity, short growing periods, and resilience under difficult agronomic conditions are key qualities that motivate farmers to include sweetpotato in their mixed farms.
When promoting biofortified nutritious sweetpotato varieties, we can build on a strong and diverse landscape of sweetpotato production in many of Asia’s and Africa’s pro-poor farming systems. In addition to supplying increased micronutrients, these varieties will still need to meet the agronomic and consumer requirements of target locations. Our strategy is to focus on those agro-ecologies and socioeconomic contexts where sweetpotato offers particular advantages over other crops and where farmers’ demand is strong. Through the RTB and A4NH CRPs, we will seek complementarity with other biofortified crops and food-based nutrition strategies.
Supporting more and more farmers to actually realize the benefits of OFSP requires continued participatory research, by CIP and our partners. Such research is needed to facilitate integration of the crop into a complex set of local systems, including crop production, water use, labor and land allocation, gender relations, food preparation and consumption, and agricultural markets. Complementing these research efforts, we will monitor and assess the scaling-up process itself in order to develop efficient and effective ways to reach large numbers of vulnerable households with OFSP and support them in making and implementing decisions about taking advantage of this technology.
In Asia, sweetpotato is not used primarily for nutrition and food security but as alternatives in industry, as livestock feed, or as high-value urban food. Our partnership with the CIP China Center for Asia and the Pacific (CCCAP) will play a pivotal role in strengthening capacity for sweetpotato—particularly in value chains—by linking pertinent Chinese expertise and experiences to demand in Asian and African target countries. Our present research collaboration with the Institute of Agro-products Processing Science and Technology at the Sichuan Academy of Agricultural Sciences will be expanded to support private sector innovations in countries where we want to foster a wider range of urban demand for nutritious sweetpotato products or where the use of roots and vines for animal feed is a priority. We will seek similar partnerships with other research, training, and innovation centers in China through the CCCAP platform beyond postharvest and animal feed work. Likewise, advances made in SSA in varietal development and delivery mechanisms will be shared with target countries in Asia through research and training partnerships between national agricultural research systems (NARS), private sector companies, and farmer associations in African and Asian countries. All scaling-up projects will include specific capacity-building and technology exchange components that will fully use CIP’s global reach to link up national and regional expertise for accelerated learning.
CIP and partners have built a strong evidence base on the nutritional efficacy of OFSP. We have developed strategic partnerships with advanced research institutions (ARIs) and delivery-focused organizations to meet the demand of expanding and diversifying the use of OFSP. Our breeding program at global and regional levels in SSA will continue to generate improved vitamin A-rich OFSP varieties and help increase iron and zinc levels through further biofortification. As discussed in the chapter on CIP’s genebank (SO 6), our OFSP germplasm includes the largest collection of sweetpotato genotypes. CIP’s OFSP germplasm, together with regionally networked germplasm facilities and expertise from the global breeding teams, is supporting increasingly effective national breeding programs. Key subregional traits such as drought tolerance, virus resistance, or low sugar content are incorporated in subregional parent populations that provide starting points for varietal development by NARS. Along with our national partners and farmers in SSA, we have developed methodologies and tools for accelerating varietal development, seed system development, intensification of production systems, and improved postharvest management, to support scaling-up of OFSP interventions in the region. Expanding and extending this network approach—to Asia in particular—will help facilitate transfer of experience, skills, and germplasm to new sites where development impacts can be achieved. Research will continue on scaling-up of breeding, seed systems, cropping system intensification, nutrition interventions, value chains, and partnership models (see section 6.1 below).
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