Doubled haploid induction in perennial ryegrass

Partners: Bruno Studer, Kirsten Vangsgaard and Niels Roulund

Project description: Attempts to implement hybrid breeding in forage grasses, such as perennial ryegrass (Lolium perenne L.), are hampered by its highly effective self-incompatibility system, which prevents efficient inbred line production by repeated selfing. The objective of this project is the development of an efficient method to obtain homozygous lines in perennial ryegrass using doubled haploid (DH) induction. By means of anther culture, completely homozygous lines can be obtained within one generation cycle. The technique has previously been described for grasses, but success is highly genotype dependent and often results in high percentages of albino plants. Genotypes with high responsiveness to anther culture have been reported and it has been shown that the trait can be crossed into breeding material. We aim at developing a molecular marker system to select for high responsiveness and to facilitate the introgression of this trait into advanced breeding germplasm.

Enlarged view: DH induction — Figures A-F. A - Harvesting spikes for anther culture. B - Spike with *L. perenne* flowers. Two mature anthers are indicated with an '*'. C - Immature anthers on induction medium. D - Embryo and callus growth on cultured anthers. E - A green shoot growing on regeneration medium. Note the albino shoot close to it. Other embryos and calli on the plate do not respond or form only roots. F - Albino shoots growing from embryos and calli on regeneration medium.