Abstract only

AC Cadillac has stem rust resistance genes Sr2 and SrCad that confer resistance to races TTKSK and TTKST. Carberry has Fhb1 providing some resistance to Fusarium head blight (FHB), but linked in repulsion to Sr2 on chromosome 3BS. Both lines have the Lr34 gene linked to Yr18. This study was conducted to determine the effect of SrCad and Sr2 loci on Fusarium head blight and to see if these loci also affect stripe rust response in a Canadian wheat background. Stripe rust and FHB were assessed in the Carberry/AC Cadillac doubled haploid (DH) population of 219 DH lines. Parents and DH lines were evaluated with molecular markers linked to Sr2 (Xgwm533 and X3B028F08) and SrCad (Xcfd49). FHB incidence and severity were evaluated in 2010 near Portage La Prairie, Canada, whereas stripe rust was rated for severity and pustule type in the 2009 rust nursery near Njoro, Kenya. AC Cadillac was resistant to stripe rust while Carberry had higher severity and pustule type ratings than AC Cadillac. The AC Cadillac Sr2 marker molecular variants were significantly associated with reduced stripe rust severity and pustule type. Association of Sr2 and stripe rust response could be due to Yr30 known to be in the Sr2 region. No significant Sr2 by SrCad interaction was observed for stripe rust response. The Carberry molecular variants for both the Sr2 and SrCad loci were associated with reduced severity and incidence of FHB. In addition to Fhb1, Carberry appeared to have another factor for resistance on chromosome 6D. Lines possessing resistance to stem rust, stripe rust and FHB were identified; lines with Fhb1, Sr2 and Yr30 in coupling will be useful for further genetic enhancement.

Global Wheat Program

English

Lucia Segura

INT2843|I1705031