Abstract

Potato (Solanum tuberosum L.) is an important food security crop in Rwanda but its productivity is low at 9 t/ha. In the past, the major potato research and development focused on seed production and distribution without targeted breeding to enhance productivity. The objective of this study was to determine yield and yield components response of potato genotypes in selected agro-ecologies of Rwanda to identify breeding parents. Fifteen agronomically stable genotypes were evaluated during 2011 at three locations: Kinigi, Rwerere and Nyamagabe with a randomised complete block design using three replications. Data were collected on yield and yield components. Further, a number of flower and tuber characteristics such as flower colour, pollen production, tuber shape, tuber flesh and skin colour, and depth of eyes were recorded. Across locations, genotype Kigega had the highest tuber yield at 32.4 t/ha, followed by Ngunda (32.3 t/ha) and Kirundo (26.9 t/ha), whereas Mabondo had the lowest yield (10.8 t/ha). At Nyamagabe genotype Kivu had the highest tuber yield of 16.7 t/ha, while Kinigi displayed the lowest at 1.8 t/ha. Genotype Ngunda was excellent yielder at Kingi with 47.2 t/ha tuber yield, while Bineza yielded low at 2.2 t/ha. At Rwerere, genotypes Victoria and Kigega were the best yielders at 45.7 and 44.7 t/ha, respectively, while Mabondo was the least yielder with 13.1 t/ha. Overall, the study identified potential breeding parents including genotypes Ngunda, Kirundo, Gikungu, Kigega, Victoria, Nderera and Bineza on the basis of medium to high responses for yield, desirable tuber characteristics and productive flowers for crosses. Location had strong effect on trait expression and contributed as the main source of variation. Genotypes Kigega and Kirundo had stable performance across locations in Rwanda. There is a need to develop potato varieties for specific agro-ecological adaptation in Rwanda.