By Christine Ochogo | christawine@yahoo.com
Sweet Potato Virus Disease which causes up to 80 per cent yield losses continues to frustrate efforts for profitable yield along the lake region in Kenya, a new report says.
Due to this constraint, the authors have called for scientists to concentrate more on breeding varieties resistant to the disease and which are at the same time drought tolerant.
The study focused on traits that Target Product Profile (TPP) for the white, orange and purple-fleshed sweet potato market segment in the Lake Victoria Crescent region in East Africa- a region that faces high virus pressure was carried out by the International Potato Center (CIP). It largely investigated relying on market intelligence to prioritize traits in breeding program.
Sweet Potato Virus Disease (SPVD) is mainly caused by the synergistic interaction of the aphid-transmitted Sweetpotato feathery mottle virus (SPFMV) and whitefly-transmitted Sweetpotato chlorotic stunt virus (SPCSV) which usually manifests itself through leaf reduction and deformation, vein clearing or mosaic, and stunting.
The study reports an approach that relies on market intelligence gathered from a broad spectrum of breeding program customers, taking market forces into account when computing trait of Economic Selection Indexes (ESIs).
The Economic Selection Index method combines both economic (Price and Value) and non- market drives in ranking traits. The ESIs then informs what traits should be pursued by breeding program.
Sweet potato breeding in Eastern Africa targets three market segments with diverse customers, including farmers, consumers, traders, and processors.
The three most preferred traits are vine survival, weevil resistance, and sweet-potato-virus disease resistance.
The sweet potato study ‘Using economic selection index for trait prioritization in sweetpotato target product profiles in Eastern Africa’ interviewed 1,000 farmers, 147 consumers, 134 traders, and 52 vine multipliers. Traders and consumers were recruited in the market, with consumers randomly selected at the point of purchase.
Its findings demonstrates that breeding for customers across the value chain has different rankings of the traits than subjective ranking, which elevates yield above all other traits in the target product profiles.
Uganda, as the host of the Eastern Africa sweet potato breeding platform, continues to influence breeding program decisions and activities for the three market segments (white, orange and purple fleshed sweetpotato) serving the region. The region’s breeding programs focus on virus resistance as the main constraint, with 18 additional essential traits and three desirable traits in the Target Product Profiles.
Sweet potatoes are ideal for child development and growth as it is crucial in the fight against Vitamin A deficiency, especially among children under the age of five and women of reproductive age.
According to International Potato Center (CIP), nutritional status of 5 million households in Africa improved through development and dissemination of vitamin A rich Orange Flesh Sweet Potato (OFSP).
The World Sweetpotato Atlas also recognizes that for over 25 years, sweetpotato has been the focus of a program underway in several countries of Africa to develop and promote new varieties high in Vitamin A.
