Introduction

Canadian Western Red Spring (CWRS) wheat is a high quality wheat with increased levels of protein that is desirable to grow. An important goal for both industry and producers is to increase CWRS production. Wheat producers in Alberta often face the challenge of short growing seasons, especially producers in the northern part of the province. The ability to create a longer growing season or to use a high-yielding, early-maturing cultivar to compensate will be really important. However, early-maturing cultivars typically produce a lower yield because they do not have the same amount of time to gather the resources required to produce high yields. In a study performed by Akther and Hassan (2011), it was found that the average number of growing degree days (GDD) in northern Alberta is about 977 which is not always sufficient (Malhi et al. 2006). Even with fewer than the ideal number of GDD it is possible to grow a CWRS crop to maturity in northern Alberta; however, it would be preferable for wheat producers if they didn't have harvest so late in the year.

Previous research has been conducted on ultra-early seeding and the results indicate that producers could integrate that practice into their management system and observe positive yield effects (Collier et al. 2021). Continuing research on this area will improve the understanding of which cultivars will perform the best if seeded into cold soils. There are several genes within wheat that affect how it will mature throughout the growing season. The VRN and PPD genes control the timing from the vegetative period to the reproductive stage in wheat plants (Whittal et al. 2018). The VRN gene is present as VRN-1, VRN-2, and VRN-3; each of those genes can be recessive or dominant. In the case of spring wheat, VRN-1 and VRN-3 are recessive and therefore the plant does not require a vernalization period or a cold treatment (Whittal et al. 2018). Winter wheat cultivars have dominant VRN-1 and VRN-3 genes and are able to survive throughout the winter in a dormant state, in fact they require overwintering so that they can flower. This cold-hardiness that is associated with winter wheat cultivars would be beneficial in protecting spring wheat under ultra-early seeding conditions. There has also been research on the development of more cold-hardy spring wheat varieties. This research has focused on crossing winter wheat and spring wheat varieties to increase the cold-hardiness of spring wheat cultivars (Collier et al. 2021). The PPD genes, or photoperiod genes, affect how the plant responds to day length and the time of flowering or anthesis. The RHT gene controls the height of the plant; in most cases, a 'semi-dwarf' plant is desirable as the plant puts less energy into the stem and more energy into the seeds.

Determining how best to utilize each cultivar in different planting scenarios is one of the main objectives of this study. The yield and quality of seed is a major component of determining how the ten cultivars should be used across the province of Alberta. Additionally, determining the genes that contribute to increased yield for ultra-early seeding; these genes include VRN, PPD, and RHT. Wheat breeders could use this information to develop wheat cultivars that are specifically designed to be used under ultra-early seeding conditions. The results of this study can be used to inform producers of which cultivar will work best in their region of the province and whether or not they might benefit from ultra-early seeding.