Abstract
Key messageBased on their consistency over environments, two QTL identified in Lillian on chromosomes 5A and 7A could be useful targets for marker assisted breeding of common bunt resistance.Common bunt of wheat (Triticum aestivum L.) caused by Tilletia tritici and T. laevis is an economically important disease because of losses in grain yield and reduced grain quality. Resistance can be quantitative, under the control of multiple small effect genes. The Canada Western Red Spring wheat variety Lillian is moderately resistant to common bunt races found on the Canadian prairies. This study was conducted to identify and map quantitative trait loci (QTL) conferring resistance against common bunt in Lillian. A doubled haploid population comprising 280 lines was developed from F1 plants of the cross of Lillian by Vesper. The lines were inoculated at seeding with the two races L16 (T. laevis) and T19 (T. tritici), grown in field near Swift Current, SK, in 2014, 2015 and 2016 and assessed for disease incidence. The lines were genotyped with the 90 K iSelect SNP genotyping assay, and a high-density genetic map was constructed. Quantitative trait locus analysis was performed with MapQTL.6® software. Two relatively stable common bunt resistance QTL, detected in two of the 3 years, were identified on chromosomes 5A and 7A from Lillian. In addition, three less stable QTL, appearing in one out of 3 years, were identified: one was contributed by Lillian on chromosome 3D and two were contributed by Vesper on chromosomes 1D and 2A. Epistatic interaction was identified for the bunt incidence between 3D and 7A resulting in greater bunt resistance. Future bunt resistance breeding will benefit from combining these QTL through gene pyramiding.
Highlights
Common bunt caused by Tilletia tritici (Bjerk.) Wint. and T. laevis Kühn is a serious disease, reducing yield and quality in wheat (Triticum aestivum L.) (Gaudet and Menzies 2012; Goates 1996; Hoffmann 1982)
A linkage map consisting of 7841 single-nucleotide polymorphism (SNP) markers spanning 3679.5 cM was built for the population using the two-step mapping strategy previously described (Fowler et al 2016; Perez-Lara et al 2016)
Simple interval mapping (SIM) followed by multiple quantitative trait loci (QTL) mapping (MQM) analysis was performed using a set of 1975 nonoverlapping SNP markers using MapQTL.6 ® (Van Ooijen 2009)
Summary
Common bunt (syn. stinking smut) caused by Tilletia tritici (Bjerk.) Wint. and T. laevis Kühn is a serious disease, reducing yield and quality in wheat (Triticum aestivum L.) (Gaudet and Menzies 2012; Goates 1996; Hoffmann 1982). T. laevis Kühn is a serious disease, reducing yield and quality in wheat (Triticum aestivum L.) (Gaudet and Menzies 2012; Goates 1996; Hoffmann 1982). Yield loss due to common bunt is approximately equivalent to the percentage of infected tillers (Menzies et al 2006). The disease remains a serious problem to wheat production worldwide despite the extensive amount of research conducted (Gaudet and Menzies 2012; Goates 1996). Common bunt is most notably a problem in organic wheat production because traditional seed treatment fungicides are not permitted (Gaudet and Menzies 2012)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
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 callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
