ARS | Publication request: Synthesis of an FHB-Resistant Durum Alien Addition Line with a Pair of Grass Chromosomes.

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: June 5, 2008
Publication Date: July 10, 2008
Citation: Jauhar, P.P. 2008. Synthesis of an FHB-Resistant Durum Alien Addition Line with a Pair of Grass Chromosomes. Meeting Abstract. The Third International Symposium on Fusarium Head Blight (FHB) Szeged, Hungary, September 1-5, 2008.

Technical Abstract: Durum wheat (Triticum turgidum L., 2n = 4x = 28; AABB genomes) is an important cereal crop widely used for human consumption. Fusarium head blight (FHB), or scab, caused by the fungus Fusarium graminearum Schwabe, is a serious disease of durum wheat. Current durum cultivars have very little or no FHB resistance. A wild relative, diploid wheatgrass Lophopyrum elongatum (Host) Á. Löve (2n = 2x = 14; EE genome) is an excellent source of resistance. By crossing durum wheat with L. elongatum we produced F1 hybrids that were sterile. By backcrossing the F1 hybrids to the durum parent, followed by selfing, we obtained several fertile hybrid derivatives with FHB resistance. We isolated a disomic addition line (2n = 28 + 2) with a pair of L. elongatum chromosomes. This alien addition line is meiotically regular and hence reproductively stable. The addition line is FHB-resistant with a mean infection = 6.5%, while the parental durum has 80% infection. Using various biochemical and molecular techniques –fluorescent genomic in situ hybridization (fl-GISH), chromosome-specific markers, Targeted Region Amplified Polymorphism (TRAP) markers, and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) – we have shown that the extra chromosome involved is 1E of L. elongatum. This is the first time that FHB resistance has been discovered on chromosome 1E. The chromosome-specific markers that we established for 1E may be used to screen fertile hybrid derivatives and durum alien addition lines for chromosome 1E that confers FHB resistance.