ARS | Publication request: SITE DIRECTED PHYSICAL AND GENETIC MAPPING OF A MAJOR QTL FOR KARNAL BUNT RESISTANCE IN WHEAT

Submitted to: Plant and Animal Genome Conference
Publication Type: Abstract Only
Publication Acceptance Date: October 15, 2003
Publication Date: January 15, 2004
Citation: Brooks, S.A., See, D.R., Singh, S., Gill, B.S., Brown Guedira, G.L. 2004. Site directed physical and genetic mapping of a major qtl for karnal bunt resistance in wheat. Plant and Animal Genome Conference.

Technical Abstract: Karnal Bunt (KB) (causal agent Tilletia indica) is an important fungal disease of wheat due to international quarantine regulations. KB was identified in the United States in the early 1990s, and is an emerging problem for Great-Plains wheat production. Germplasm resources are available for enhancement of disease resistance in US adapted wheat varieties. A major QTL for KB resistance was mapped to the long arm of chromosome 4B in spring wheat line HD29 from India. Two microsatellite markers linked to this QTL were physically mapped to deletion bin 4BL10-0.95-1.00 of Chinese Spring wheat, positioning the QTL in the distal 5% of the chromosome arm. A targeted approach was used to identify ESTs located in the distal region of wheat chromosome 4BL based upon microsynteny to the short arm of rice chromosome 3. Thirty-two ESTs physically mapped to the 4BL-10 bin, will be mapped genetically in a HD29 x WL711 RIL population. Polymorphic markers linked to the KB QTL will be used to identify additional markers in the QTL region based upon rice synteny. Markers flanking the KB resistance QTL will be converted to PCR based markers for marker-assisted selection in US wheat breeding programs.