Summer‐survival cultivars of Italian ryegrass (Lolium multiflorum Lam.) potentially contain Festuca genome fragments.

Italian ryegrass (Lolium multiflorum Lam.) cultivars vary widely in their persistence; there are very early heading annual types as well as very late heading, summer‐survival types that survive for 2 or 3 years. Hybrid cultivars that survive in summer temperatures are bred using genes of a similar species (Festuca) in combination with Lolium. It is hypothesized that commercial summer‐survival cultivars of Italian ryegrass include Festuca genome fragments. In this report, we investigated the genomic constitution of five summer‐survival cultivars using the genomic in situ hybridization technique. Two out of the five cultivars contained Festuca genome fragments, confirming that summer‐survival cultivars may include Festuca genome fragments. [ABSTRACT FROM AUTHOR]