Location: Cereal Crops Research
Project Number: 3060-21000-037-26-T
Project Type: Trust
Start Date: Oct 15, 2012
End Date: Oct 14, 2017
Septoria tritici is one of the most devastating foliar diseases of wheat, especially in Europe. The objectives of this proposal are to 1) develop high-throughput markers suitable for the marker-assisted selection and initiation of the map-based cloning of the Stb16 Septoria tritici resistance gene, and 2) screen collections of synthetic hexaploid wheats, hexaploid landraces, and wild relatives to identify novel sources of Septoria tritici resistance.
For objective 1, a doubled haploid population consisting of 170 progeny derived from the wheat line ND495 and the synthetic hexaploid wheat line TA4152-19 (NC19 population) has been used to initiate the saturation mapping of the Stb16 gene on chromosome arm 3DL. This population, developed at the USDA-ARS RRVARC in Fargo, ND, will be used to develop a saturated linkage map of the Stb16 locus using previously developed markers. Also, new markers will be developed based on bin-mapped ESTs, BAC end sequences, and high-throughput survey sequences available for the wheat genome. Following the construction of a saturated genetic map, high-resolution mapping will be conducted in a population of 5,000 F2 plants derived from the same parents. Markers identified to be tightly linked to the Stb16 locus will be subjected to high-throughput platforms for breeding purposes, and will be used to initiate physical map development, map-based cloning, and further marker development for the Stb16 locus. For objective 2, large collections of synthetic hexaploid, landraces, and wild relatives will be screened for reaction to Septoria tritici at both the juvenile and adult plant stages. Resistant accessions will be further screened with the appropriate isolates and genotyped to determine if they harbor novel resistance genes. Accessions with novel resistances will be incorporated into breeding programs and used to develop new populations for further genetic analysis.