A comparison of univariate and multivariate methods to analyze G x E interaction

Twenty-two different methods (parametric, nonparametric and multivariate) used for analysing genotype X environment (G X E) interaction were compared by applying them to two sets of experimental data (15 faba bean cultivars X 12 environments and 11 pea cultivars X 16 environments). A principal components analysis was performed on the rank correlation matrix arising from the application of each method. The 22 methods can be categorized, in both sets of experimental data, in three groups: (1) those which are mostly associated with yield level and show little or no correlation with stability parameters; (2) those in which both yield level and stability of performance are considered simultaneously to reduce the effect of G x E interaction; and (3) those methods which only measure stability. This analysis also separated those methods based on an agronomic concept of stability from those which are based on a biological one, as well as distinguishing between 'dynamic' and 'static' stability-based methods. (C) 1998 Elsevier Science B.V.