Hamito, Desta(PhD)Kassa, Legesse2018-06-272023-11-092018-06-272023-11-091997-06http://10.90.10.223:4000/handle/123456789/3826Tllis study was designed to attain a better understanding of envirollllental factors such as soil and climate that could account for variation in grain yield and component characters of tef genotypes, Furthennore, it was intended to determine the source of variability in the relationships among grain yield and component characters within and among tef genotypes. In the study, 7 and 4 variables of soil and climate, respectively were collected from four locations for the crop seasons 1991/92, 1992/93 and 1993/94. Five plant variables of 12 tef genotypes were also collected for the same locations and crop seasons. Combined analysis of variance, analysis of variance components, canorucal correlation analysis and principal component analysis were used to analyse the data, The results of the study, based on combined analysis of variance and analysis of variance components, revealed that soil and climate variables accounted for a large portion of the variation in grain yield and component characters of tef genotypes. The results of canonical correlation analysis also supported this fact. The results of principal component analysis showed that each of the genotype variables considered in this study had their own share of contribution to the variation within and among genotypes.enAssessment of Environmental EffectsThesis