Submitted to: Seed Production Research at Oregon State University
Publication Type: Experiment Station
Publication Acceptance Date: 3/31/2006
Publication Date: 4/30/2006
Citation: Cooper, L., Barker, R.E., Warnke, S.E., Brown, R. 2006. Using advances in plant genomics to develop a DNA-based test to benefit the ryegrass seed industry. Seed Production Research at Oregon State University. EXT/CrS 125, 4/06 pages 48-51
Interpretive Summary: The majority of the worldwide supply of perennial (Lolium perenne L.) and annual (or Italian) (L. multiflorum) ryegrass seed is produced in Oregon’s Willamette Valley. Perennial ryegrass is grown mainly for turf production, while the annual cultivars are primarily used for forage. Identifying annual ryegrass contamination in perennial ryegrass seed lots has been of major interest in the seed industry for many years. Knowledge of genes controlling differences between annual and perennial specific physical plant types would help in understanding genetic relationships among species and perhaps assist breeders in forage and turfgrass improvement programs. We have identified several major candidate genes that can be used in a multi-point genomic test to distinguish the two growth types. The protocols we are developing will be verified and validated in cooperation with the Oregon Seed Certification Service, the Oregon Seed Testing Lab, other University and Commercial Seed Testing Labs, and the OSU Extension Service.
Technical Abstract: Annual (Lolium multiflorum Lam.) and perennial (Lolium perenne L.) ryegrasses are two common forage species in temperate regions. Identifying annual ryegrass contamination in perennial ryegrass seed lots has been of major interest in the seed industry for many years. The objective of our work over the past few years has been to identify the genetic basis of the differences in growth habit between the annual and perennial ryegrasses. A candidate for the primary vernalization response gene (LpVrn-1) has been identified and we are currently working on isolating and genetically mapping candidates for the second vernalization gene, LpVrn-2. We have developed a DNA test for the first vernalization gene (LpVrn-1) based on a DNA sequence difference between the annual cultivar ‘Gulf’ and the perennial cultivar ‘Manhattan’. We have also made considerable progress towards identifying the Lolium candidate of the second vernalization gene Vrn-2, which represses flowering until the cold period is met. We have begun developing possible test protocols in our lab. The protocols include multi-locations in the genome to "triangulate" on more accurate detection of ryegrass growth types.