Improvement of grain yield and quality in climate change resilient crops

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The high anthropogenic activities during the last century has elevated the atmospheric carbon dioxide levels, increased air temperatures and altered the precipitation patterns around the globe; these climate changes present serious challenges to crop productivity. To maintain food and nutritional security, worldwide increase in crop yield and improved nutritional quality is needed. For Canada, the required improvements include wheat (Triticum aestivum L.), which is a staple in the human diet and an important export commodity for Canadian producers. ***Canada is a major wheat producer and exporter with average annual production of ~30 million metric tons over the last five years and accounts for $5 billion dollar in export revenue. In Canada, the three Prairie Provinces account for 84% of the arable land and primary producers of wheat. Spring wheat (~83%) is the dominant type grown in Canada. However, in years with low winter kill, fall seeded winter wheat produces 20 40% higher yield than spring wheat. Winter wheat is also a very environmentally friendly crop as it efficiently uses spring moisture, matures early and yields more than spring wheat. During the last decade of research, using genomic selection, we have characterized wheat genotypes with increased cold tolerance and improved winter survival compared to the most hardy winter wheat cultivar Norstar. The next step in our research program is to combine the high winter hardiness trait with increased yields and improved grain quality to make new winter wheat cultivars more attractive for wheat growers. An important component of grain yield is seed size that is mainly affected by the plant's source-sink relationship, genetic factors determining the early stages of seed development and environment. Recent studies show that the maternal tissues surrounding the growing seed set the limit to seed growth and size in wheat. To develop strategies to increase seed size, we will analyze early seed development in a winter wheat population (>800 recombinant inbred lines, RIL) varying in seed size and combine it with genotypic data obtained by genotyping by sequencing to develop genetic maps. The genetic maps will be used to identify the genomic regions, characterize the candidate genes to analyze the genetic factors and regulatory networks associated with early seed development. The basic knowledge will be used to develop genetic markers for use by wheat breeders in genomics assisted selection to combine optimal alleles for seed size and grain quality into cold hardy winter wheat lines to increase yield and improve their grain quality. ***Successful completion of the project will result in identification of winter-hardy wheat lines with improved seed size and quality for cultivar development. Winter wheat with high winter hardiness, large seed size/yield and improved seed quality are needed for food security and for the Canadian producers to stay competitive on the international wheat market. **