|Rouse, Matthew - Matt|
|CAI, XIWEN - North Dakota State University|
Submitted to: Annual International Plant & Animal Genome Conference
Publication Type: Abstract Only
Publication Acceptance Date: 10/27/2014
Publication Date: 1/10/2015
Citation: Xu, S.S., Friesen, T.L., Chao, S., Jin, Y., Rouse, M.N., Faris, J.D., Cai, X. 2015. Targeted introgression of stem rust Ug99 resistance from wheatgrasses into pasta and bread wheat [abstract]. Plant & Animal Genome XXIII, January 10-14, 2015, San Diego, CA. Available: https://pag.confex.com/pag/xxiii/webprogram/Paper14596.html.
Technical Abstract: In the past 50 years, a number of stem rust resistance (Sr) genes have been transferred from several wheat-related grasses into durum (i.e. pasta) and bread wheat through chromosome translocations and additions. To utilize these genes for controlling the Ug99 races of the stem rust pathogen, we initiated this research to reduce linkage drag associated with four Ug99-resistance genes (Sr37 from Triticum timopheevii, Sr39 and Sr47 from Aegilops speltoides, and Sr43 from Thinopyrum ponticum)) and to transfer novel Sr genes from four wheat-alien species (Ae. markgrafii, Th. intermedium, and Th. junceum) disomic addition lines into the wheat genome. To minimize linkage drag, we first developed a large homoeologous recombinant population using the ph1b mutant in hexaploid wheat and a Ph1-deficient stock in durum wheat. Homoeologous recombinants carrying the Sr genes on reduced alien chromosomal segments were identified using high-throughput phenotyping and genotyping. By using this procedure, we developed wheat germplasm carrying the four Sr genes (Sr37, Sr39, Sr43, and Sr47) on small alien chromosomal segments. To transfer novel Sr genes from the wheat-alien species addition lines, we used 'Chinese Spring' Ph1 inhibitor or monosomics to induce recombination between wheat chromosomes and their homoeologs carrying the Sr genes from alien species. New wheat lines containing four novel Sr genes on translocated alien chromosome segments were developed from the crosses of the wheat-alien species addition lines with the Ph1 inhibitor or monosomics. The new wheat lines developed in this study provide useful resources for the ongoing global breeding efforts to combat Ug99.