Some Aspects of Stability of Crop Varieties

1. Introduction The performance of a particular variety is the result of its genetic constitution and the environment in which it has been grown. In practice it is quite possible that a particular variety may not exhibit the same phenotypic performance under different environments or different varieties may respond differently to a specific environment. This variation, arising from the lack of correspondence between the genetic and non-genetic effects is known as the genotype-environment (GE) interaction. The presence of GE interaction reduces the correlation between phenotype and genotype, makes difficult to judge the genetic potential of variety and alters the relative ranking of different varieties. Because of these very reasons, before the successful release of particular variety on commercial basis plant breeders grow different varieties at different locations over the years just to determine the magnitude of GE interactions for ensuring the stability of varieties, under varying environments.