Homoeologous chromosome pairing provides an opportunity to introgress chromosome segment from one species to another. On the other hand, it may cause destabilization of hybrid genome via formation of multivalents and univlents, and consequntly, the loss of chromosomes and/or uneven segregation. We developed hybrids of Mediterranean and Continental morphotypes of tall fescue (Festuca arundinacea Schreb.) with aim to introgress summer dormancy from the former morphotype to latter. However, reduction in seed set has been evidenced as a consequence of incompatibility of meiotic control systems being present in both parents and hampers further utilization of the amphiploid hybrids. We hypothesize that backcross steps will be necessary to restore proper chromosome pairing and fertility.