Project Component #1 Introducing beta-carotene rich sweet potato clones
Background information
Worldwide, sweet potato is the sixth most important food crop after rice, wheat, potatoes, maize, and cassava. But in developing countries, it is the fifth most important food crop. More than 105 million metric tons are produced globally each year; 95% of which are grown in developing countries. Sweet potato can grow at altitudes ranging from sea level to 2,500 meters. It requires fewer inputs and less labor than other crops such as maize, and tolerates marginal growing conditions (e.g., dry spells, poor soil). Sweet potato comes in varieties with skin and flesh color that range from white to yellow, orange, and deep purple. Sweet potatoes produce more edible energy per hectare per day than wheat, rice or cassava. They are good sources of carbohydrates, fiber, and micronutrients. The leaves and shoots, which are also edible, are good sources of vitamins A, C, and B (Riboflavin). Orange-fleshed sweet potato is an important source of beta-carotene, the precursor to vitamin A. Just 125g of fresh sweet potato roots from most orange-fleshed varieties contain enough beta-carotene to provide the daily pro- vitamin-A needs of a preschooler. Sweet potato is also a valuable source of vitamins B, C, and E, and it contains moderate levels of iron and zinc. Nutritionists in the United States are exploring the potential cancer-preventing properties of the anthocyanins, which are present in purple-fleshed sweet potato. Though its origins lie in Latin America, Asia is now the largest sweet potato-producing region in the world, with figures showing over 90 million tons produced annually. China is the world’s biggest producer and consumer of sweet potato, where it is used for food, animal feed, and processing (as food, starch, and other products).
The importance of sweet potato as a food crop is growing rapidly in some parts of the world. In Sub-Saharan Africa, it is outpacing the growth rate of other staples. Sweet potato is used for both human consumption and as a healthy, cheap source of animal feed. Recent studies suggest that animals fed on high protein sweet potato vines produce less methane gas than with other feed, potentially contributing an important reduction in harmful global emissions. Sweet potato has a long history as a lifesaver in disaster relief. The Japanese used it when typhoons demolished their rice fields. It kept millions from starvation in famine-plagued China in the early 1960’s and came to the rescue in Uganda in the 1990’s, when a virus ravaged cassava crops.
Activities to be implemented
- Organize four small nurseries for production of sweet potato vines where, at maximum, three nutritious and promising varieties of sweet potato will be multiplied.
- Organize up to 12 small demonstration plots where those varieties will be tested for yielding capacity and suitability for local conditions.
- Support registration of sweet potato clones and recommendation for production.
- Develop a technical guide for growing sweet potato in the Khatlon region in the Tajik language, based on the observation of demonstration plots.
- Train TAWA agricultural staff and other local agriculture extension specialists in sweet potato production.
- Organize open field days and other training sessions, based on training needs assessment conducted.
- Organize cooking quality testing events of sweet potato.
- Develop promotional materials for publishing, focused on the promotion of sweet potatoes in schools and kindergartens.
Results to be achieved
- At least two new sweet potato varieties with high levels of beta-carotene and the best agronomic characteristics suitable for local conditions introduced, tested in farms, and recommended and registered or prepared for registration in Tajikistan.
- Sweet potato integrated into diets as part of household food security.
- At least one local farmer in each district will have the capacity to produce sweet potato vines and transfer this technology to other local farmers.
- Local agricultural specialist’s knowledge and experience in the production of sweet potato increased.