GENOTYPE-ENVIRONMENT INTERACTION IN FABA BEAN - COMPARISON OF AMMI AND PRINCIPAL COORDINATE MODELS

This study analyses the genotype-by-environment (G x E) interaction of 11 genotypes of Vicia faba L., grown in 17 environments in Andalucia (Southern Spain) by two multivariate methods (AMMI and Principal Coord inate Analysis). Results of the stability analyses indicated that the most stable genotypes for resistance were not the same as those for yi eld. However three, L1, L2 and VF1071, were by far the most Orobanche- resistant materials and were as productive as well-established cultiva rs, but their yields showed low stability among environments. Progress in selection for both Orobanche resistance and yield is hampered by l arge environmental variation between locations. More breeding effort i s needed in these three experimental genotypes in order to improve the yield stability and therefore acceptability to farmers. Multivariate analysis has shown its advantage as a helpful tool in identifying the best genotypes for a new cycles of crossing and selection. For the cul tivars and environments analyzed in this study, the two methods gave e qually satisfactory results in detecting cultivars that perform well a nd remain stable under different environment conditions.