Low crown rust resistance in Norwegian material of Lolium perenne and ×Festulolium

Norwegian cultivars and breeding materials of perennial ryegrass and Festulolium were planted at three locations in Denmark, France and Japan for test-ing of resistance against leaf diseases. In general, all plant materials were susceptible to crown rust. The highest incidence of rust attack occurred at the French site, which due to its climatic conditions might be the most suitable testing site for future scoring of similar plant material. Entries based on introgressed genetic materials from UK were most resistant towards crown rust. Crown rust resistance needs increased focus as a breeding objective in the Nordic region due to climate changes, which will most likely lead to increased infection of leaf diseases.