ARS | Publication request: SYNTHESIS OF AN FHB-RESISTANT DISOMIC DURUM ALIEN ADDITION LINE WITH A PAIR OF DIPLOID WHEATGRASS CHROMOSOMES

Submitted to: Cereal Research Communications
Publication Type: Proceedings/Symposium
Publication Acceptance Date: August 1, 2008
Publication Date: September 1, 2008
Citation: Jauhar, P.P. 2008. Synthesis of an fhb-resistant disomic durum alien addition line with a pair of diploid wheatgrass chromosomes. Cereal Research Communications. 36 (B):77-82

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 ravaging 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 of 6.5%, while the parental durum has 80% infection. Using various biochemical and molecular techniques ¿ fluorescent genomic in situ hybridization (fl-GISH) and chromosome-specific markers ¿ 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.