Abstract

An experiment to partition the component of variation in selected hybrid of Arabica coffee was conducted at two different locations in South-western region of Ethiopia. Genetic variation, genotype × environment interaction of 15 quantitative morphological characters, was studied in fifteen Arabica coffee hybrids including two standard checks. The hybrids were evaluated at three to four environments (location-by-year combinations). The randomized complete block design was used in each environment. Data were collected on an individual tree basis for all traits except for yield, measured on a plot basis and converted to individual tree basis for statistical analysis. Results attained by this study showed that moderate genetic variation was detected only for four agro-morphological traits of hybrid coffee genotypes, the remaining traits had shown low genetic variation. Some of the traits were under strong influence of environment than genetic as revealed by high range of variation across environments than genotypes. The traits that had a low ratio of σ2ge/σ2g also showed a moderate value for heritability. For traits, stem girth, canopy diameter, length of primary branches and reaction to coffee leaf rust incidence, with a low G x E interaction and moderate heritability, selection can be done at any of the environments within Mid-lowland coffee agro-ecology in early breeding stages with high selection efficiency. Thus, these traits can be confirmed at the breeding site.