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Additional index words. Ipomoea batatas, sweetpotato virus disease, alternaria bataticola blight, provitamin A Two sweetpotato [Ipomoea batatas L. (Lam.)] cultivars, NASPOT 12 O (Namulonge sweetpotato 12 orange-fleshed) and NASPOT 13 O (Namulonge sweetpotato 13 orange-fleshed) were approved for release by the Ugandan Plant Variety Release Committee (UPVRC) in Nov. 2013(Ssemakula et al., 2013. This brings to 22, the number of sweetpotato cultivars officially released between 1999 and 2013 by the National Sweetpotato Program in Uganda (Mwanga et al., 2011;Ssemakula et al., 2013). The two cultivars herein described and released in 2013, have high average storage root yields, 43.1 t • ha -1 ('NASPOT 12 O') and 27.8 t • ha -1 ('NASPOT 13 O') on station, and 14.9 t • ha -1 ('NASPOT 12 O') and 9.7 t • ha -1 ('NASPOT 13 O') on farm compared with the national on-farm average for Uganda of 4.5 t • ha -1 (FAOSTAT 2010;Low et al., 2009). The cultivars have acceptable root shape, high dry matter content (DMC) (>30%) with

Additional index words. seedling screening, sweetpotato breeding, sweetpotato virus disease, Alternaria bataticola blight The sweetpotato [Ipomoea batatas (L.) Lam.] cultivar NASPOT 11 (Namulonge Sweetpotato 11) was approved for release by the Ugandan Plant Variety Release Committee in Apr. 2010 (Mwanga et al., 2010). This is the fifth time the sweetpotato breeding program in Uganda has officially released sweetpotato cultivars. The program released 19 cultivars between 1995 and 1999 (Mwanga et al., 2009), but to the best of our knowledge, 'NASPOT 11' represents the first sweetpotato cultivar bred from segregating populations by participatory plant breeding (PPB) for Africa and perhaps the world (Gibson et al., 2008; Mwanga et al., 2010). 'NASPOT 11' has acceptable storage root shape (long elliptic) when grown in light soils, has high dry matter (DM) (%34%), and good to excellent consumer acceptance, depending on growth conditions. The cultivar has moderate to high field resistance to sweetpotato virus disease (SPVD) and Alternaria bataticola blight.

The National Sweetpotato Programme of the National Agricultural Research Organisation (NARO) in Uganda released 14 sweetpotato cultivars between 1994 and 2005. Of the released cultivars, six have gained importance in local Ugandan markets and in export trade to Europe and two are being used as parental sources for high dry matter (>30%), sweetpotato virus disease (SPVD) and nematode resistance in hybridization schemes, and in the genetic mapping work in joint international collaborative research. Two orange-fleshed sweetpotato (OFSP) cultivars, namely, Ejumula, and SPK004 (Kakamega), high in beta-carotene (the precursor for vitamin A) are spreading rapidly for combating widespread vitamin A deficiency in Uganda. The major steps leading to the release of Kakemega and Ejumula are used to illustrate the experience of the Ugandan sweetpotato breeding programme sustained activities for a decade, and lessons learnt are highlighted. The sustained breeding activities have led to a vibrant and robust program, increased international and south to south collaboration, increased partnership and alliances; shifted research focus from production to production per se and quality (nutrition), resulting into significant and relevant agricultural research. The lesson here is that it takes a long time to develop technologies, disseminate and commercialize them. It also requires commitment by the donor, government, scientists, farmers and other stakeholders for effective commercialization of the developed technologies.