Start Date: May 13, 2009
End Date: May 12, 2014
Project Title 1: Crosses will be made between and among FHB resistance sources and regionally adapted germplasm. We plan to screen about 2,700 breeding lines from our program, including about 2,000 F5 lines, 400 preliminary yield trial lines, 200 advanced yield trial lines and varieties, and 100 other lines with very high levels of FHB resistance. We will also screen the Uniform Regional Scab Nursery in two field nurseries. All of these lines will be tested in at least two inoculated/misted field nurseries in 2009 and more advanced materials in three nurseries. Approximately 25 named varieties and 10-15 pre-release lines are tested each year for yield performance at 7 Minnesota locations. This information is not only useful to growers for variety selection on their own farm, but also for breeding programs regionally and globally for selection of parents for crossing. About 50 highly resistant lines from the germplasm introgression project will be evaluated in the FHB nurseries in 2009. We plan to submit ~1,000 F5 samples for marker assisted selection. Pre-screening any new resistance source (predominantly from the germplasm project currently funded through the former HGR), allows us to avoid materials containing these QTLs and focus our attention on materials containing potentially novel QTL. Project Title 2: One hundred and fifty F6-derived RIL from the cross Wheaton/PI 81971 are being used for QTL mapping. Phenotyping is complete and more than 200 SSRs have been mapped on a subset of 94 individuals. Markers in genomic regions suspected to be near FHB QTLs based on the analysis using 94 RILs will be assayed on the remaining 56 RILs to obtain a more accurate estimate of QTL effects. We developed a unique approach to QTL validation that is amenable to direct incorporation into breeding activities (Pumphrey et al., 2007). Currently, 11 F3 populations from cross combinations involving four highly resistant RILs from the Wheaton/PI 81971 population and three adapted spring wheat lines are available and advanced to the F4 generation for field screening in 2008 for agronomic screening before extracting QTL-NILs using markers. Homozygous QTL NILs will be developed from selected lines in 2009 in and evaluated to assess QTL effects in point inoculation trials in the greenhouse in Fall 2009 and Spring 2010 and field studies in 2010.