ARS | Publication request: Mapping Growth Habit Traits in Elymus Wheatgrasses

Submitted to: International Symposium on Molecular Breeding of Forage Crops Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: June 27, 2007
Publication Date: July 1, 2007
Citation: Mott, I.W., Larson, S.R., Robins, J.G. 2007. Mapping Growth Habit Traits in Elymus Wheatgrasses. International Symposium on Molecular Breeding of Forage Crops Proceedings.

Technical Abstract: Thickspike wheatgrass (Elymus lanceolatus) and Snake River wheatgrass (Elymus wawawaiensis) are perennial grasses common to the Great Plains and Intermountain regions of the Western United States. E. lanceolatus (EL) is a drought-tolerant rhizomatous grass that is valued for its forage qualities and conservation purposes. E. wawawaiensis (EW) is a highly palatable bunch-type forage grass. To identify genetic loci controlling rhizome growth-habit in Elymus wheatgrasses, four full-sib mapping populations were developed by backcrossing four EL x EW hybrids to the same EL recurrent parent. Four full-sib backcross populations have been produced consisting of 346 total individuals. Replicated field evaluations of growth habit, plant height, and other morphological traits have been completed at one site, and further data for growth habit, biomass and forage quality will be collected from two additional locations. A genetic map covering the 14 linkage groups of the Elymus genome has been constructed from more than 600 AFLP markers along with nearly 100 SSR anchor markers designed from bluebunch wheatgrass (Pseudoroegneria spicata) and Elymus EST sequences. The SSR marker sequences were aligned to the rice genome so that genotyping could be targeted to specific linkage groups on the Elymus map to ensure complete coverage of each chromosome. Specific attention was given to linkage group 3 (rice chromosome 1) that is hypothesized to contain a major QTL controlling rhizomes in other species such as Leymus wildryes. The current status of the mapping project will be presented.