Two pairs of sister lines of hexaploid triticale (X Triti-cosecale Wittmack) differing by the presence ( + + ) or absence ( - ) of telomerrc heterochromatin on chromosome arms 7 RL (cv. Drira) and 6 RS (cv. Rosner) were used in order to study the effects of telomeric heterochromatin loss on twelve agronomic traits. The following multivariate statistical techniques were used : multivariate analysis of variance, partial correlation, multiple regression analysis and canonical correlation. The loss of telomeric heterochromatin was accompanied by significant changes in the means of the twelve traits as a whole as evidenced by the results of the multivariate analysis of variance and in the regression of yield on the other traits. Many more partial correlation coefficients were changed in the Drira lines than in the Rosner lines ; most coefficients became larger in the Rosner line lacking heterochromatin while the opposite was true in the corresponding Drira line. The traits most affected differed from cultivar to cultivar.