Plant & Animal Genomes XV Conference

January 13-17, 2007
Town & Country Convention Center
San Diego, CA

Using DArT And SSR Markers For QTL Mapping Of Fusarium Head Blight Resistance In Six-Row Barley.

Marie-Eve Rheault , Cindy Dallaire , Suzanne Marchand , Liyi Zhang , Martin Lacroix , Francois Belzile

  Department of Plant Sciences, Laval University, Québec City QC Canada G1K 7P4

The development of barley (Hordeum vulgare) cultivars with resistance to Fusarium head blight is difficult due to the complex inheritance of FHB resistance. Identification of QTLs for FHB severity and DON level would provide the basis for marker-assisted selection and facilitate the selection of resistant lines. A segregating population of 293 doubled haploid lines was developed from a cross between two six-row barleys: ACCA, a relatively susceptible elite cultivar, and Chevron, classified as « moderately resistant ». Doubled haploid lines and their parents were inoculated under field conditions at the experimental station of Laval University (Québec, Canada). Inoculations were done by spraying heads with a conidial suspension of Fusarium graminearum strain Fg9903. Over six years (2000-2005), a randomized complete block design with three replications was employed. In the field, spikes were visually assessed for FHB infection 15 days after inoculation. In 2002, 2003, 2004, seed harvested were tested for DON levels using an ELISA test. A combination of DArT and SSR markers was used to map QTLs associated with FHB severity and DON levels. The use of DArT markers proved extremely useful in adding a large number of markers (>200) in very little time.