Development of hormone based genomic tools to accelerate wheat breeding for enhanced preharvest sprouting tolerance

开发基于激素的基因组工具，加速小麦育种，增强收获前发芽耐受性

• 批准号: 493479-2015
• 负责人: Ayele, Belay
• 金额: $ 2.29万
• 依托单位: University of Manitoba
• 依托单位国家: 加拿大
• 项目类别: Collaborative Research and Development Grants
• 财政年份: 2017
• 资助国家: 加拿大
• 起止时间: 2017-01-01 至 2018-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=619060
• 关键词: Development; hormone; based; genomic; tools

Wheat is one of the most economically important crops of Canada, however, its production is challenged constantly by a variety of stress factors such as preharvest sprouting (PHS), which refers to the germination of grains on the mother plant prior to harvest. PHS lowers grain yield and severely limits end-use quality, causing substantial economic loss to the producers. Given that the incidence of PHS is expected to increase with climate change induced seasonal shifts in precipitation and temperature, tolerance to PHS is a highly desirable trait sought by Canadian wheat producers. Many of the genetic and environmental factors that regulate PHS tolerance are mediated mainly by abscisic acid (ABA) and gibberellins (GA), which are among the plant produced compounds that influence growth and developmental processes at very low concentrations, usually coined as "plant hormones". ABA and GA play antagonistic roles in controlling PHS; ABA enhances PHS tolerance while GA promotes PHS potential. However, how environmental factors such as temperature regulate the balance of grain ABA/GA levels and sensitivity during maturation, and thereby PHS tolerance is poorly understood in wheat. Difference in PHS tolerance between wheat genotypes can also be induced by variations in the genomic sequences and/or expression levels of key genes implicated in the control of PHS. The goals of this research are to identify specific molecular elements that regulate temperature-induced changes in ABA/GA balance in maturing wheat grains, identify PHS associated variations in the sequences of ABA related genes, and investigate temperature regulation of other key PHS controlling genetic factors. The findings of this research will provide powerful genomic tools that can facilitate the breeding of wheat cultivars with adequate PHS tolerance; thereby improving wheat yield and quality, and farm income for Canadian wheat producers. Further, this research involves the training of highly qualified personnel in the area of crop biotechnology and molecular breeding, which is critical to the competitiveness of Canada's crop industry.

小麦是加拿大最重要的经济作物之一，但其产量不断受到各种胁迫因素的挑战，如穗发芽(PHS)，即收获前母株上的谷物萌发。小灵通降低了粮食产量，严重限制了最终使用质量，给生产者造成了巨大的经济损失。由于PHS的发病率预计会随着气候变化引起的降水和温度的季节性变化而增加，因此对PHS的耐受性是加拿大小麦生产者非常希望获得的特性。许多调节PHS耐性的遗传和环境因素主要由脱落酸(ABA)和赤霉素(GA)介导，它们是植物产生的化合物之一，在很低的浓度下影响生长和发育过程，通常被称为“植物激素”。ABA和GA在控制PHS中起拮抗作用，ABA提高PHS耐性，而GA促进PHS潜力。然而，温度等环境因素如何调节籽粒成熟过程中ABA/GA水平的平衡和敏感性，从而影响小麦对PHS的耐性，目前尚不清楚。小麦对PHS耐性的差异也可以由基因组序列的差异和/或与PHS相关的关键基因的表达水平的差异引起。本研究的目的是确定调控温度诱导的小麦成熟籽粒ABA/GA平衡变化的特定分子元件，识别与PHS相关的ABA相关基因序列变异，并研究其他关键的PHS控制遗传因素的温度调节。本研究结果将为选育耐PHS的小麦品种提供有力的基因组工具，从而提高小麦的产量和品质，提高加拿大小麦生产者的收入。此外，这项研究还涉及培训作物生物技术和分子育种领域的高素质人员，这对加拿大农作物行业的竞争力至关重要。