Enhancing traits of agronomic and economic importance in wheat

小麦是加拿大最重要的经济作物之一。然而，它的生产不断受到各种因素的挑战，包括收获前发芽（PHS），这是指收获前种子在亲本植物上发芽，以及倒伏，这是指作物倒伏，通常在穗出现后，由于大风和大雨。这些因素结合在一起，导致粮食产量和质量显著下降，给小麦生产者带来巨大的经济损失。在商品小麦生产中，倒伏的发生率与氮肥用量的增加有关，而氮肥用量的增加对获得更高产量至关重要。虽然化学生长调节剂可以控制作物高度并减轻倒伏问题，但由于其对生产者的额外成本以及相关的环境和食品安全问题，它们的使用是不可持续的。大多数商业小麦品种已被选定为种子休眠，以达到快速和均匀的发芽和快速的立场建立，因此，他们容易受到PHS时，潮湿的条件下发生收获前。有利于PHS的环境条件的严重性和频率预计将随着气候变化而增加。因此，加拿大小麦生产商寻求耐倒伏和PHS的小麦品种。种子休眠和茎高/强度主要由植物激素调节，然而，小麦中的潜在分子机制知之甚少。小麦基因型间PHS和抗倒性的差异也可归因于分别作为种子休眠和茎高/强度的关键调节因子的遗传因素。然而，控制小麦这些性状的遗传机制却很少被研究。拟议的研究旨在确定新的基因/等位基因，可作为基因组工具，以促进小麦育种，增强对PHS和倒伏的耐受性，从而提高产量和质量，并最大限度地提高加拿大小麦生产者的经济回报。

Wheat is one of the most economically important crops of Canada. However, its production is constantly challenged by a variety of factors including preharvest sprouting (PHS), which refers to germination of seeds on the parent plant prior to harvest, and lodging, which refers to falling over of the crop, often after ear emergence, due to high wind and rain. These factors in combination cause significant reduction in grain yield and quality, incurring high financial loss to wheat producers. The incidence of lodging in commercial wheat production is associated with increased usage of nitrogen fertilizers that is essential for attaining higher yields. Although chemical growth regulators can control crop height and mitigate the problem of lodging, their use is not sustainable due to its considerable additional cost to the producers and the associated environmental and food safety concerns. Most of the commercial wheat cultivars have been selected against seed dormancy to attain fast and uniform germination and rapid stand establishment, and as the result they are susceptible to PHS when wet conditions occur prior to harvest. The severity and frequency of environmental conditions that favor PHS are expected to increase with climate change. As a result, wheat cultivars with tolerance to lodging and PHS are sought by Canadian wheat producers. Seed dormancy and stem height/strength are regulated primarily by plant hormones; however, the underlying molecular mechanisms are poorly understood in wheat. Variation in PHS and lodging tolerance between wheat genotypes can also be attributed to genetic factors that act as key regulators of seed dormancy and stem height/strength, respectively. Nonetheless, the genetic mechanisms controlling these traits in wheat are scarcely studied. The proposed research is aimed at identifying novel genes/alleles that can be deployed as genomic tools to facilitate wheat breeding for enhanced tolerance to PHS and lodging, and thereby improve yield and quality and maximize economic returns to Canadian wheat producers.