Yield Response and Late Blight Reaction of Potato Genotypes in Rwanda

Potato (Solanum tuberosum L.) genotypes with relatively high yield level and resistance to the late blight disease are being developed by the International Potato Centre (CIP) and made available to developing countries. However, for effective breeding for high yield and late blight resistance, these CIP materials and locally adapted genotypes need to be evaluated and screened under target growing environmental conditions. The objectives of the study were to determine yield response and late blight resistance of potato genotypes grown in Rwanda and candidate clones obtained from CIP and to identify suitable parents for breeding. A total of 44 potato genotypes, 30 acquired from CIP and 14 local varieties were evaluated under three environments (Kinigi, Rwerere and Nyamagabe). Experiments were laid out in an 11 × 4 alpha lattice design with two replications. Data were collected on late blight severity (%) based on the relative area under the disease progress curve (RAUDPC: 100 % max), total tuber yield, marketable tuber weight and dry matter content. Genotypes had significant differences on blight resistance and yield levels among test locations. Eight genotypes (391,047.34, 393,385.39, 393,280.82, 396,036.201, Gikungu, Ngunda, Kigega and Nderera) were identified as promising parents for subsequent crosses. The selected genotypes display farmers-preferred traits, productive flowers, high to medium late blight resistance and high yields.