Submitted to: Journal of Plant Registrations
Publication Type: Peer reviewed journal
Publication Acceptance Date: 7/11/2007
Publication Date: 7/15/2007
Citation: Jauhar, P.P., Peterson, T.S. 2007. Dge-1, a durum alien disomic addition line with resistance to fusarium head blight. Journal of Plant Registration 2:167-168. Interpretive Summary: Scab or Fusarium head blight (FHB) is a devastating disease of both bread wheat and durum or macaroni wheat, causing huge losses to farmers. There is no scab resistance in current wheat cultivars. Earlier, we found that a wild grass, called diploid wheatgrass (Lophopyrum elongatum), is highly resistant to scab. By crossing a durum cultivar, Langdon, with the grass we transferred a pair of grass chromosomes (rod-like structures that carry the genes of interest) into durum wheat and produced scab-resistant durum germplasm that we call "disomic addition line." This line is stable and shows less than 21% scab infection, while the parent cultivar Langdon has almost 80% infection. This line, named DGE-1, is being released for distribution to durum breeders and other researchers for basic and applied research on FHB.
Technical Abstract: Scab or Fusarium head blight (FHB), caused by the fungus Fusarium graminearum Schwabe., is a serious disease of durum wheat (Triticum turgidum L., 2n = 4x = 28; AABB genomes) and current durum cultivars have almost no FHB resistance. Because diploid wheatgrass, Lophopyrum elongatum (2n = 2x = 14; EE genome) is highly resistant to FHB, we crossed the durum cultivar Langdon with this grass. The F1 hybrids were sterile. We produced, by backcrossing to the recurrent durum parent, followed by selfing, several hybrid derivatives with 80% or higher seed fertility. These hybrid derivatives were screened for scab resistance. The hybrid material with one or more grass chromosomes showed high resistance to scab (less than 21% infection). We have isolated a disomic addition line, DGE-1 (2n = 28 + 2) with full chromosome complement of durum plus a pair of alien chromosomes from L. elongatum. PCR using L. elongatum chromosome-specific markers showed the added chromosome to be 1E of L. elongatum. Because this line forms 15 bivalents (14 of durum and one of L. elongatum) during meiosis it is meiotically regular and hence reproductively stable. This addition line has 21% FHB infection compared to 80% in the Langdon parent. The disomic addition will be useful for basic and applied research on FHB.