Exploring genomic selection as a tool to improve the accuracy and speed of breeding in barley

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Barley constitutes an important crop in Québec and is well adapted to the cooler climate found in the central and easternmost farmlands of the St-Lawrence valley. Despite a favourable environment, the cropping area devoted to this cereal has declined over the past decade. This is, in part, attributed to the challenges faced by farmers in dealing with Fusarium head blight (FHB), a devastating fungal disease. The disease leads to a loss of grain quality due to the presence of a highly toxic compound, the mycotoxin deoxynivalenol or DON, that is produced by Fusarium spp directly inside an infected kernel. Although there are now fungicides that can be used to limit the damage caused by this disease, they are costly and their application is tricky as the window for application is very narrow. For this reason, farmers would prefer to use cultivars that offer a good level of FHB resistance and thereby limit the need to apply fungicides unless conditions are extremely favourable to the fungus. Developing improved cultivars with increased FHB resistance is, however, hugely challenging because of the difficulties faced in accurately assessing the genetic resistance of barley lines during the development of new cultivars. In this proposed work, we aim to explore novel approaches to more accurately predict the true level of genetic resistance to FHB among barley lines using a genomics approach, one in which the genetic composition of a line is used to predict its level of resistance. This approach could be used both to identify the most promising lines among large numbers of progeny derived from a cross between two barley lines, but also to guide the breeder in selecting which crosses have the potential to generate the best offspring. Should this endeavour prove successful, it would represent a tremendous step forward in barley breeding as this "genomic selection" approach could be applied not only to FHB resistance but to other agronomic traits of interest. As FHB resistance is the number one problem facing barley production, any innovation allowing the development of improved varieties with increased resistance to this disease could bring considerable economic and food safety benefits to this crop that is grown on 2.5M hectares in Canada, second only to wheat and canola.