Abstract
CIMMYT wheat (Triticum aestivum L.) lines Francolin#1 and Quaiu#3 displayed effective and stable adult plant resistance (APR) to Chinese Blumeria graminis f. sp. tritici isolates in the field. To elucidate their genetic basis of resistance, two recombinant inbred line (RIL) populations of their crosses with Avocet, the susceptible parent, were phenotyped in Zhengzhou and Shangqiu in the 2014–2015 and 2015–2016 cropping seasons. These populations were also genotyped with SSR (simple sequence repeat markers) and DArT (diversity arrays technology) markers. Two common significant quantitative trait loci (QTL) on wheat chromosomes 1BL and 4BL were detected in both populations by joint and individual inclusive composite interval mapping, explaining 20.3–28.7% and 9.6–15.9% of the phenotypic variance in Avocet × Francolin#1 and 4.8–11.5% and 10.8–18.9% in Avocet × Quaiu#3, respectively. Additional QTL were mapped on chromosomes 1DL and 5BL in Avocet × Francolin#1 and on 2DL and 6BS in Avocet × Quaiu#3. Among these, QPm.heau-1DL is probably a novel APR gene contributing 6.1–8.5% of total phenotypic variance. The QTL on 1BL corresponds to the pleiotropic multi-pathogen resistance gene Yr29/Lr46/Pm39, whereas the QTL on 2DL maps to a similar region where stripe rust resistance gene Yr54 is located. The QTL identified can potentially be used for the improvement of powdery mildew and rust resistance in wheat breeding.
Highlights
Powdery mildew (PM), caused by Blumeria graminis f. sp. tritici (Bgt), is a significant disease of common wheat worldwide, reported to have caused yield losses of up to 34% (Alam et al, 2011)
Francolin#1 and Quaiu#3 were susceptible to Chinese Bgt isolates E09 and E20 at the seedling stage, but showed resistance at the adult plant stage
The recombinant inbred line (RIL) from both populations were susceptible in seedling stage
Summary
Powdery mildew (PM), caused by Blumeria graminis f. sp. tritici (Bgt), is a significant disease of common wheat worldwide, reported to have caused yield losses of up to 34% (Alam et al, 2011). Race-specific resistance genes were widely applied in Chinese wheat breeding because of their high level of effectiveness through all growth stages of the crop. These genes are known to break down readily due to the selection of pathogen isolates with matching virulence genes. The multi-pathogen resistances conferred by Pm38 and Pm46 encode a putative ABC transporter and a hexose transporter (Krattinger et al, 2009; Risk et al, 2012; Moore et al, 2015), respectively These pleiotropic APR genes are valuable in wheat breeding for their broad effectiveness and potential durability
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
