DURUM-WHEAT QUALITY EVALUATION - INFLUENCE OF GENOTYPE AND ENVIRONMENT

Protein content and gluten quality (alveograph W) were determined for 21 durum wheat cultivars grown in several locations in Italy from 1990 to 1993. Cultivars and sites were not the same in all years, but thre e cultivars that are considered as standards were used to link all ana lyzed data. Each site-year combination constituted an environment. The effect of genotype, environment, and their interaction on protein con tent and alveograph W,which are the most important variables in predic ting pasta cooking quality, were studied. Protein content was essentia lly determined by additive effects of environment, whereas alveograph W appeared more influenced by additive effects of genotype. Genotype-e nvironment (GE) interaction for both the variables was significant but small in magnitude when compared with the additive effects of genotyp e and environment. The majority of cultivars appeared stable; coeffici ent of regression was equal to one, and deviation from regression mean square was negligible. The large additive effects of environment and genotype and the small GE interaction provide efficiency in the select ion of new lines grown in only one environment and allow the average q uality of a cultivar to be established by compositing samples over man y locations.