The generation of wheat/Aegilops umbellulata wild relative lines and characterisation of their traits associated with high protein content and disease

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The challenges of maintaining sufficient food production for a growing world population is immense. Climate change, pests and diseases, food quality and nutrition are all challenges that need to be met and overcome to ensure food security. Wheat, which feeds over 2.5 billion people world-wide (wheat.org) providing 20-50% of daily calorie intake (Ceoloni et al. 2017) and 20% of protein consumption in wheat growing areas, has insufficient natural genetic variation which stemmed from a genetic selection pressure during domestication (Fu and Somers 2009). The limited genetic variation will make it difficult in the future to increase biotic and abiotic stress tolerances and to improve quality traits such as protein levels for bread production. The biofortification of wheat is also of increasing importance, with 'hidden hunger' affecting approximately two billion people through nutrient deficiency (world health organisation 2006). Wheat wild relatives were not subjected to this genetic bottle neck, so they still convey many of the traits that wheat requires. These wild relatives are a major source of untapped genetic variation which can be transferred into wheat by crossing (introgressing) them together to introduce alleles from the wild relative.Aegilops umbellulata is one of these wild relatives. With the genome UU, this wild relative is known to convey diversity for traits such as high protein content suitable for bread making (Liu et al. 2003) and to increase processing and nutritional qualities of bread wheat (Kumar et al. 2019). Ae.umbellulata has also been shown to contain higher iron and zinc levels (Neelam et al. 2012) and, for leaf and stem rust resistances, which can cause a devastating decrease in wheat yields (60-100%) worldwide ((Park 2007), (Bansal et al. 2020). This project will transfer genetic variation from Ae. umbellulata into wheat by crossing wheat with Ae. umbellulata and then backcrossing for several generations until each line is mostly wheat but contains a small segment of genetic material from Ae. umbellulata. The aim is to produce a set of wheat/Ae. umbellulata lines, each plant containing a different small homozygous segment covering the 7 chromosomes of Ae. umbellulata, suitable to test for traits of interest.The introgressions will be validated using cytogenetic techniques and KASP marker genotyping to find the position and size of the transferred material (Grewal et al. 2020). The genetically stable homozygous lines can then be bulked and tested for desirable traits. In particular, the lines will be screened for rust resistances (Fellers et al 2020), by Professor John Fellers at Kansas State University with the opportunity to visit Kansas for analysis. Depending on the progression of the project, other traits may also be tested at Nottingham University, e.g., agronomy benefits, photosynthetic traits, high grain protein content or mineral (Fe, Zn) content. This could potentially produce much needed genetic diversity for wheat breeders and help solve the challenges of food security. Novel publications could include the generation of the introgression lines and their characterisation using GISH and KASP markers, and trait analysis of the lines.