Potato is one of the important crops grown in mid and high altitude areas of Ethiopia. Several
potato genotypes has been introduced and tested in different parts of the region. However, the stability
and performance of these genotypes under different parts of the region is not yet assessed. Therefore, the
objective of this study was to determine the effect of genotype, environment and their interaction for tuber
yield and identify stable potato genotypes. The study was conducted using eight potato genotypes under
rainfed production season of 2010 and 2011at five potato growing areas of the region. Randomized
complete block design with three replications was used for the experiment. Among the testing locations,
the superior mean tuber yield (25.43t/ha) was obtained from Adet while the inferior (13.89t/ha) was from
Injibara. Similarly, among the genotypes CIP- 396004.337 had high mean tuber yield(25.66t/ha), while
CIP-395011.2 had inferior mean tuber yield. Combined ANOVA indicated that the main effect due to
environments, genotype and genotype by environment interaction were highly significant for tuber yield.
The contribution of E, G and GEI for the total variation in tuber yield was about 47.11%, 8.83% and
44.07% respectively .The GEI was further partitioned using GGE biplot model. The first two principal
components obtained by singular value decomposition of the centered data of tuber yield explained
71.04% of the total variability caused by (G+GE). Out of these variations PC1 and PC2 accounted
50.98% and 20.07% respectively. Generally, GGE biplot view of this study identified Serinka and CIP-
396004.337 as ideal testing location and genotype respectively in the region.