Principles of Genetics and Breeding

11.1.12 Environmental deviation

• Environment is all non-genetic influence on the phenotypic value.
• It is assumed that the genotype is conferring a certain value on the individual and environment is causing a deviation from this in one direction or the other.
• Hence, it is known as environmental deviation in the population and as a whole is taken to be zero, so that mean phenotypic value is equal to the mean genotype in a number of individuals and measure them under environmental conditions normal for the population.
• The mean environmental deviation would be equal to the genotypic value.