Improvement of grain yield and quality in climate change resilient crops

上个世纪高度的人为活动提高了大气中的二氧化碳水平，提高了气温，改变了全球的降水模式；这些气候变化对作物生产力构成了严峻的挑战。为了维持粮食和营养安全，需要在世界范围内提高作物产量和改善营养质量。对加拿大来说，需要改进的包括小麦(Triticum aestivum L.)，这是人类饮食中的主食，也是加拿大生产者的重要出口商品。*加拿大是小麦的主要生产国和出口国，过去五年的平均年产量约为3000万吨，出口收入为50亿美元。在加拿大，草原三省占84%的可耕地和小麦的初级生产者。春小麦(~83%)是加拿大的主要种植类型。然而，在冬害少的年份，秋播冬小麦产量比春小麦高20-40%。冬小麦也是一种非常环保的作物，因为它能有效利用春季水分，成熟早，产量高于春小麦。在过去十年的研究中，利用基因组选择，我们已经确定了与最耐寒的冬小麦品种Norstar相比，具有更强的耐寒性和更好的冬季存活率的小麦基因型。我们下一步的研究计划是将高抗寒性与增产和改善籽粒品质相结合，使冬小麦新品种对小麦种植者更具吸引力。谷物产量的一个重要组成部分是种子大小，它主要受植物的源库关系、决定种子发育早期阶段的遗传因素和环境的影响。最近的研究表明，生长中的种子周围的母体组织限制了小麦种子的生长和大小。为了开发增加种子大小的策略，我们将分析种子大小不同的冬小麦群体(&gt；800重组自交系，RIL)的早期种子发育，并将其与通过测序进行基因分型获得的基因数据相结合，以开发遗传图谱。这些遗传图谱将被用来识别基因组区域，表征候选基因，以分析与早期种子发育相关的遗传因素和调控网络。这些基础知识将用于开发遗传标记，供小麦育种者在基因组学辅助选择中使用，将种子大小和籽粒品质的最佳等位基因组合到抗寒冬小麦品系中，以提高产量和改善其籽粒品质。*该项目的成功完成将导致识别出种子大小和质量都得到改善的冬小麦品系，以用于品种开发。为了粮食安全和加拿大生产商在国际小麦市场上保持竞争力，需要具有高抗寒性、大籽粒/产量和改善种子质量的冬小麦。**

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. **