Agricultural scientists at the National Crops Resources Research Institute (NaCRRI) at Namulonge in Wakiso district are laying strategies to popularize a number of highly nutritious potato varieties including the ‘wonder’ purple-fleshed sweet potato in Uganda and the East and Central Africa sub-region.

The varieties are preferred for their multi-purpose roles including treatment of health complications like cancer-related diseases.  

 The varieties marked for popularizing include the purple-fleshed sweet potato, the orange-fleshed sweet potato varieties including ‘ejumula’, ‘Kakamega’, ‘NASPOT 9’, ‘NASPOT 13’, NASPOT 8, NASPOT 12, NASPOT 11, and NASPOT 10.  

Dr. Ephraim Nuwamanya, senior research officer at the nutrition and biotechnology laboratory said that many of the sweet potato varieties bred at Namulonge are aimed at helping people to eat highly nutritious foods that are relevant for their life.

He said the purple-fleshed sweet potato, for example, is instrumental for families especially children and breastfeeding mothers for their high value in nutrition ingredients.

He said the ‘purple color’ in the sweet potato is because it has ‘anthocyanin’, which is a key component in reducing the incidents of diseases such as cancer.

Although the purple-fleshed sweet potato is still unknown in many parts of Uganda and the region, he said, it also offers other purposes like in industries where the color is extracted and used to colour foods like ice cream, yoghurt, and cakes, among others.   

Dr. Nuwamanya and other scientists made the revelations during a five-day benchmarking exercise for scientists from eight countries from the East and Central Africa in Uganda to visit the National Agricultural Research Organisation (NARO) affiliated institutes, under which Uganda is a member of the Association for Strengthening Agricultural Research in Eastern and Central Africa (ASARECA).

The project is funded by the European Union and the countries that sent delegates to include Burundi, Cameroun, Central African Republic, Democratic Republic of Congo, Eritrea, Madagascar, Republic of Congo, South Sudan, and Sudan. 

According to Nuwamanya, the purple-fleshed sweet potato variety is already with the farmers in Uganda and many have tasted and liked it although they have not popularized it enough to be found in local markets in the capital city of Kampala. “The purple-fleshed sweet potato, although it has not been given a variety name, once it is popularized, it will help our society to solve many problems,” he explained.   

The orange-fleshed sweet potato varieties, Nuwamanya stated, are important as well for nutrition and they have been developed in Uganda so far using people ‘germplasm’ that has been sought from abroad.

The materials have been crossed with the local varieties and the results have been helpful in giving good properties in the sweet potatoes related to improving nutrition, health and helping children to get better food for a population free of diseases.   

Nuwamanya asked the visiting scientists to adopt the tools that Uganda is using so that they can be able to embrace the variety as fast as they can.  He also asked parents in Uganda who have large families to start growing the purple sweet potato saying they won’t go wrong to get the nutrition they need in terms of calories, energy, and starch.

He said families will also get micronutrients that are lacking in most of the foods that people eat in Uganda like posho (maize flour) rice and others. “So if families can have sweet potatoes with improved nutrients then they will get much more benefits as parents,” he said, adding it will reduce disease burdens in the homes and ensure children live a good life. 

Joshua Okonya, program officer technology, and innovation at ASARECA also had good comments about the purple-fleshed sweet potatoes and other varieties. He said the Purple-flashed sweet potato has food ingredients and compounds that help bodies to fight cancer and pressure-related complications, which he said was the reason why it is being popularized and promoted in Uganda. It also has anti-oxidants, he said, that support the body to boost immunity.   

They are also promoting other varieties like the white-fleshed color potatoes, which are preferred by many farmers because they look similar to what they already grow in their gardens and are known to be tolerant to diseases. They also yield well and stay longer in the garden but, he stressed, don’t contain vitamin A, which is vital for human health.

 

“But NARO has bred varieties that are deep-orange inside or light orange. The deep orange varieties have a higher content of carotene, a precursor for vitamin A, which helps to improve eyesight and is important for pregnant women and children under five. We have a lot of projects to create awareness in several districts in Uganda and working with a number of partners to promote them and trying to establish potato vine multiplication sites from where farmers can access them,” he explained.

He said the white variety is hard and similar to cassava but as the orange color deepens the variety becomes soft. 

“The deeper the orange, the softer it becomes. But the less the orange the less the betacaroteen (an organic strongly colored red-orange pigment abundant in plants),” he said.

He added that the older people are used to white and hard varieties and tend to resist the orange because it is softer and if cooked for a longer time, it can marsh whereas children and women like it because of the color but also they benefit because they stand higher chances of suffering from vitamin A deficiency. He said Uganda suffers high levels of vitamin A deficiency up to 35%.  

“We encourage delegates that as Uganda is willing to share knowledge with the different research institutes in the region and develop an exchange program to let them take the materials back to their countries and test them with their local environments.