Plant & Animal Genomes XI Conference

January 11-15, 2003
Town & Country Convention Center
San Diego, CA

Workshop: Abiotic Stress
            

MINING BARLEY FOR GENES DETERMINING WINTER HARDINESS PHENOTYPES

Department of Crop and Soil Science, College of Agriculture, Oregon State University, Corvallis, OR 97331

The development of winter hardy malting barley varieties will offer the US malting industry an alternative source of supply and growers an alternative crop. Considerable effort has been invested in quantitative trait loci (QTL) analysis of the major traits (e.g., low temperature tolerance, vernalization requirement, photoperiod response) influencing barley winter hardiness. A major barley cold tolerance QTL cluster has been identified on chromosome 7 (5H). Recent studies in Arabidopsis and other dicots have demonstrated that members of the CBF/DREB gene family act as key regulators of plant cold tolerance and other stress responses. We have cloned eight barley CBF gene family members to date and have mapped four of the barley CBF genes directly adjacent to the major cold tolerance QTL region; the four CBF members are present as a clustered gene family. The size of the barley CBF gene family and response of each member to cold, drought, salt, day-length, and hormone exposure is being investigated. Assignment of map positions for the remaining barley CBF genes, as well as saturation of this area with additional markers, is in progress. A barley BAC clone has been mapped to a position directly under the cold tolerance QTL peak, and overlapping BAC clones identified as a first step towards a chromosome walk across the QTL region. A set of 59 DM near-isogenic lines is being densely genotyped to define the segments of chromosome 7(5H) that play a central role in conveying the low temperature tolerance phenotype