APPLICATION OF A GENERALIZED GRUBBS MODEL IN THE ANALYSIS OF GENOTYPE-ENVIRONMENT INTERACTION

The presence of genotype-environment interaction is a common feature o f yield trial data. Estimating variance components attributable to the interactions of single cultivars is a useful means of assessing pheno typic stability. The stability variance is one such measure. In this p aper it is argued that the stability variance is appropriate only if t he error variances are homogeneous across genotypes and the number of replicates is the same in each environment. An alternative is suggeste d for the case that either of these two assumptions is violated.