The genome of bread wheat, AABBDD, was substituted into the cytoplasm of Hordeum chilense by repeated backcrossing to produce alloplasmic lines. The aim of this work was to investigate the effect of H. chilense cytoplasm on agronomic traits in common wheat. Three cytolines were developed. The alloplasmic nature of these lines was confirmed using chloroplast simple]sequence repeat markers. Each cytoline was compared with its respective euplasmic control for agronomic performance during 2 years of field trials. The interaction between H. chilense cytoplasm and common wheat genome greatly affected most of the traits evaluated. Among them, alloplasmic lines showed delayed anthesis date, lower yield and lower plant height. These effects are similar to those caused by Aegilops cytoplasm. The main conclusion of this work is that H. chilense cytoplasm is of limited value for wheat breeding.