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Rooting Out Hunger with Vitamin A Orange fleshed sweet potato | Harvest Plus


Washington D.C., August 8, 2012: A study published today in the Journal of Nutrition provides conclusive evidence that orange sweet potato (OSP) provided significant amounts of vitamin A to malnourished Ugandan children and women and that a modest improvement in vitamin A levels in the body was measurable in some cases.

Vitamin A deficiency (VAD) is a major public health concern in poorer countries and accounts for more than 600,000 deaths a year among children under five years of age. In Africa, VAD prevalence is estimated at 42% among children under five.

Uganda is among the African countries reported to be at high risk, with 28% of children and 23% of women estimated to be vitamin A deficient. VAD can impair immunity and cause eye damage that can lead to blindness and even death. Annually, up to 500,000 preschool children go blind from VAD, and about two-thirds will die within months of going blind.

Biofortification is the process of breeding new varieties of foods crops that contain higher amounts of nutrients to improve nutrition and public health. Agricultural approaches, such as biofortification, are now being looked upon to fill the nutritional gap for vitamin A and other nutrients.

Traditionally, white or yellow sweet potato varieties are grown and eaten in Africa, but these provide little, or no, vitamin A. OSP was conventionally bred, not just to provide more vitamin A but also to be high yielding and drought tolerant.

From 2007–2009, HarvestPlus and its partners disseminated new OSPvarieties to more than 10,000 farming households in Uganda for whom sweet potato is a key staple food. The project provided OSP vines for farmers to grow, as well as extension services and nutritional information so that farmers could incorporate OSP into their cropping systems. Since sweet potato is available for about 10 months a year, it can be a rich and steady source of vitamin A.

The project resulted in 61% of households adopting the vitamin A-rich OSP to grow on their farms. They were also willing to substitute more than one-third of their traditional white and yellow sweet potato consumption with OSP. This level of substitution was enough to push large numbers of children and women over the threshold, ensuring that their daily requirements for vitamin A were met.

Vitamin A intake increased by two-thirds for older children and nearly doubled for younger children and women by project end. For children 6–35 months, who are especially vulnerable, OSP contributed more than 50% of their total vitamin A intake.

The high prevalence of inadequate vitamin A intake among a subset of children 12–35 months who were no longer breastfeeding fell from nearly 50% to only 12% as a result of the project. This is a very positive finding as young children who have recently stopped breastfeeding are at higher risk ofVAD. This is because breast milk has been their primary source of vitamin A and their vitamin A needs continue to be high.

Researchers were also able to measure a small positive impact of eating OSPon the amount of vitamin A in the blood among children 5–7 years that had lower levels of vitamin A at the start of the project. At project end, researchers also found that women who got more vitamin A from OSP had a lower likelihood of having marginal VAD. (VAD was unexpectedly low among the women sampled in this study, thus making it harder to detect changes.)

“Overall, these results add to the growing evidence base that OSP provides large amounts of vitamin A in the diet,” says Dr. Christine Hotz, former HarvestPlus Nutrition Head who led the nutrition study. “We were also able to show a modest increase in vitamin A blood levels among children, despite this being challenging to measure given the changing nutritional landscape over two years under real-world conditions.”

This project was undertaken concurrently in Mozambique where results showed even higher levels of adoption—and consumption—of OSP by vulnerable households.

“We now have evidence from two very different countries and contexts that show that farming households are willing to adopt OSP, incorporate it in their diets, and get the vitamin A that they need,” says senior IFPRI economist, Dr. Daniel Gilligan.

HarvestPlus is now scaling-up OSP to reach another 225,000 households by 2016. The International Potato Center (CIP) plans to scale-up OSP to reach more than 600,000 households in 10 countries by 2015, including 120,000 households in Mozambique.

About the Project
From 2007-2009, HarvestPlus and its partners disseminated orange sweet potato—to see if VAD could be reduced—to more than 24,000 households in Mozambique and Uganda. HarvestPlus leads a global effort to breed and disseminate micronutrient-rich staple food crops to reduce hidden hunger in malnourished populations. It is part of the CGIAR Research Program on Agriculture for Nutrition and Health (A4NH). It is coordinated by the International Center for Tropical Agriculture (CIAT) and the International Food Policy Research Institute (IFPRI).

Journal Article
Introduction of β-Carotene–Rich Orange Sweet Potato in Rural Uganda Results in Increased Vitamin A Intakes among Children and Women and Improved Vitamin A Status among ChildrenJournal of Nutrition.

Partners in Uganda
Association for Strengthening Agricultural Research in Eastern and Central Africa (ASARECA) and Regional Potato and Sweetpotato Improvement Network in Eastern and Central Africa (PRAPACE), Farming for Food and Development Eastern Uganda (FADEP-EU), International Food Policy Research Institute, International Potato Center (CIP), Makerere University, National Agricultural Research Organization, Natural Resources Institute, University of Greenwich, Uganda Bureau of Statistics, Volunteer Efforts for Development Concerns (VEDCO). Thanks go to the district and provincial officials in Uganda (Bukedea, Kamuli, Mukono) and to the many people of Uganda who participated in the project and the research study.

The Bill and Melinda Gates Foundation provided a direct grant that made this research possible. Additional HarvestPlus core funding was also used to support this work, which included support from (in alphabetical order): Denmark (DANIDA), Sweden (SIDA), the Syngenta Foundation, the United Kingdom (DFID), the United States (USAID), and the World Bank.

HarvestPlus leads a global effort to breed and disseminate nutrient-rich staple food crops to reduce hidden hunger globally. It is part of the CGIARResearch Program on Agriculture for Nutrition and Health (A4NH). It is coordinated by the International Center for Tropical Agriculture (CIAT) and the International Food Policy Research Institute (IFPRI)

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Posted by on August 13, 2012 in General


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The Importance and Challenge of rapid multiplication of Vegetative Crops in Africa |

This is a kumara (a kind of sweet potato). Deu...

Kumara (a kind of sweet potato).

Realizing the potential of Africa’s vegetative crops requires new tools for rapid multiplication of healthy and improved planting material 

Bananas, plantains, cassava, potato and sweet-potato, as well as other indigenous African root vegetables are key in solving Africa’s food and income security challenges. The total production of these crops almost doubles that of maize, rice and wheat in Africa. These vegetatively propagated crops are an excellent source of cheap energy and are a key staple foods in Sub-Saharan Africa. The importance of these crops is well known for example East African Highland bananas in the African Great Lakes region, and Cassava and Plantains in West Africa. Some cultivars are very nutritious because they are rich in vitamins or essential minerals. Research shows that a family of five could meet their annual vitamin A requirements from only a small 10 x 50 meter plot of recently developed orange flesh sweet-potato, even at low yield levels of around 5 tonnes per hectare.

Root and vegetative crops such as these are mostly produced, processed, and traded in farm households or locally, making them less vulnerable than grain to abrupt price changes in international markets. Cassava and sweet-potato can be grown in marginal conditions and nontraditional areas, and can be produced with relatively few inputs because of their ability to tolerate many abiotic stresses such as drought or heat or poor soils. In some agro-ecosystems, they often complement cereals to cut risk and make more efficient use of resources by providing food earlier in the farming calendar or by be planted in otherwise fallow periods between grain crops. They are also known as “famine crops” because of their particular role during the “lean or hunger season” when their tuberous roots can be harvested as needed to meet shortfalls in grain.  and other vegetative crops. A uniquely African Green Revolution requires urgent improvements in the supply of  new and improved cultivars of these vegetative crops.

Multiplication and dissemination of new varieties requires new innovation in greenhouse, tissue-culture, micro-propagation and decentralized field multiplications of healthy planting materials. In Africa today, farmer or commercial multiplication of these crops is very low compared with multiplication of cereal and pulse seed. Most planting materials used by farmers are often of poor quality because they are infected with pests and diseases, which perpetuate (and exacerbate) pest losses through successive growth cycles. Newly developed higher yielding, or disease and pest tolerant cultivars, have not been made available in sufficient and reliable quantities to satisfy the demands of African growers.

The best strategy to deliver healthy planting materials for vegetatively propagated crops includes micro-propagation of healthy propagules of selected germplasm along with multiplication in greenhouses, shade-houses and field plots. Micro-propagation is the process of growing tissue culture for plant shoot-tips in a laboratory until they are ready for transplant into the field. This propagation system significantly reduces pathogen incidence and may dramatically improve yield when coupled with good agronomic practices. Micro-propagation systems can easily include quality control to ensure certification and delivery of “clean” propagules. Tissue culture-derived materials can rapidly grow, helping  the introduction of newly bred germplasm at reasonable cost and speed.  They are also amenable to biological enhancement (e.g. with endophytes that extend the benefits of “clean” planting material) before delivery to farmers. Macro-propagation will be further use to multiply additional clean planting material locally and at a lower cost. However, when re‐infection rates are high, a continual supply of new planting material will be a must for annual or biennial replanting or these vegetatively propagated crops.

Phytosanitary testing to support schemes for certifying the quality of such materials throughout the production chain will be also a key element for this rapid multiplication system. The production, conditioning, and marketing of certified planting materials will be the responsibility of the public or private grower but the certifying agency must verify that they follow the approved regulations outlined by the national authority to meet the required standards for certification.

African Seed Network
Guest Contribution by Rodomiro Ortiz, PhD
Professor, Genetics and Plant Breeding
Swedish University of Agricultural Sciences (SLU), Alnarp, Sweden

Rodomiro Ortiz worked as researcher at UNALM, CIP (Perú), Rutgers Univ. (USA) and IITA (Nigeria), held a Nordic professorship in plant genetic resources at the Univ. Copenhagen (Denmark), and director at ICRISAT (India), IITA and CIMMYT (México).

Posted by on April 12, 2012 in General


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