Androgenesis from a Lolium multiflorum x Festuca arundinacea hybrid to generate extreme variation for freezing-tolerance

New opportunities for plant breeding using androgenesis in Lolium x Festuca hybrids have been identified. Plants derived by anther culture from a Lolium multiflorum x Festuca arundinacea (5x) hybrid were screened for freezing-tolerance, and their post-freezing recovery compared. The androgenic population showed extreme diversity in freezing-tolerance. While the majority of androgenic plants had inferior freezing-tolerance compared with the freezing-sensitive L. multiflorum parent, 6% of the population were more freezing resistant than the freezing-tolerant Festuca parent. Novel Lolium and Festuca gene combinations resulting from rare meiotic events were recovered within the androgenic population. The two most freezing-tolerant androgenic plants carried virtually the entire F. pratensis subgenome of F. arundinacea. F. pratensis is known to carry genes for freezing-tolerance and would be expected to be the primary source of genes governing this trait within the F. arundinacea genome. The most freezing-tolerant androgenic plants were more freezing-tolerant than the hybrid plant from which they were derived. Consequently, androgenesis was also effective in removing factor(s) reducing the expression of freezing-tolerance within the L. multiflorum x F. arundinacea (5x) hybrid.