|Participatory sweetpotato breeding and germplasm evaluation for resistance to viral and fungal diseases|
R. O. MWANGA (1), R. W. Gibson (2), G. N. Ssemakula (3), C. G. Yencho (4). (1) International Potato Center, Kampala, Uganda; (2) Natural Resources Institute, Kent, United Kingdom; (3) National Agricultural Research Organization (NARO), Kampala, Uganda; (4) North Carolina State University, Raleigh, NC, U.S.A.
<i>Sweetpotato is important for calories and provitamin A in developing economies. Propagated vegetatively, sweetpotato can accumulate pathogens, resulting in reduced yield losses (50 to >90%), prompting breeding for increased disease resistance. Scientists and farmers in Uganda identified preferred cultivars through participatory varietal selection, and new clones from seedling populations through a participatory plant breeding (PPB) approach. Farmers identified 51 attributes of their landraces or released varieties and used 21 criteria to select clones from seedling populations. Scientists had a shorter list of attributes; some cultivar attributes important to farmers were overlooked by scientists. The process of PPB in farmers’ fields amongst a scientist-derived seedling population led to the eventual official release of the sweetpotato cultivar, NASPOT 11 (Tomulabula), in 2010 in Uganda. NASPOT 11 had high Alternaria blight resistance in field trials under high inoculum pressure at Kachwekano. Sweetpotato virus disease (SPVD) resistance and tolerance were confirmed by scientists in quantitative reverse transcription polymerase chain reaction assays. NASPOT 11 is also high yielding, with high dry matter content (>30%) and is now widely grown in Uganda.</i>