Genetic characterization of the triticum-stagonospora nodorum pathosystem

植物病害对加拿大的大田和园艺作物造成重大经济损失，影响到从生产者到消费者的整个加拿大经济。植物产品的数量和质量下降造成直接经济损失，但病原体产生的影响人类和动物健康的毒素也可能造成间接损失。真菌病原体引起大多数植物病害，并且已经进化出成功感染其植物宿主的不同策略。一种策略是坏死性营养，其中真菌在真菌入侵之前或期间杀死宿主组织。从死亡的宿主组织中提取营养物质供真菌生长和繁殖。毒素的产生是坏死营养型真菌致病的关键决定因素。这项研究计划的长期目标是揭示坏死营养型真菌病原体与其植物宿主之间相互作用的分子基础。本研究以小麦-节孢霉（Stagonospora nodorum）致病系统作为模式致病系统。S.颖壳针孢（Septoria nodorum）是加拿大普通小麦（Triticum aestivum）和硬粒小麦（Triticum turgidum subspecies durum）的一种常见的坏死型病原体，引起颖壳针孢斑点病（Stagonospora nodorum blotch，SNB）。本研究的主要目的是：1）利用S. 2）鉴定赋予SNB抗性的小麦基因。将使用连锁和关联作图策略的组合来研究宿主-病原体相互作用的遗传学。连锁作图是一种可靠的遗传分析方法，已广泛应用于植物和真菌的遗传研究。关联作图是一种新的基因作图方法，广泛应用于人类和动物的遗传学研究。这些研究将为深入了解坏死营养型病原体的毒力和致病性的遗传基础，并确定和表征宿主中的抗性基因提供帮助。这些信息将推进这一学科的科学知识，并在抗病作物的育种中应用。

Plant diseases cause significant economic losses to field and horticultural crops in Canada, affecting the entire Canadian economy from producers to consumers. Direct financial losses result from decreased quantity and quality of plant produce, but indirect costs can result from pathogen-produced toxins that affect human and animal health. Fungal pathogens cause the majority of plant diseases and have evolved different strategies for successfully infecting their plant hosts. One strategy is necrotrophy, where the fungus kills host tissue before or during fungal invasion. Nutrients are extracted from the dead host tissue for fungal growth and reproduction. The production of toxins is a key determinant of pathogenesis for necrotrophic fungi. The long-term goal of this research program is to uncover the molecular basis of interactions between necrotrophic fungal pathogens and their plant hosts. The Triticum-Stagonospora nodorum pathosystem will be used in this research as a model pathosystem. S. nodorum (synonym Septoria nodorum, teleomorph Phaeosphaeria nodorum) is a common necrotrophic pathogen of Triticum aestivum (common wheat) and Triticum turgidum subspecies durum (durum wheat) in Canada, and causes the leaf spotting disease stagonospora nodorum blotch (SNB). The main objectives of this program are: 1) the identification of the fungal genes involved in the pathogenesis of Triticum species by S. nodorum and 2) identification of Triticum genes conferring SNB resistance. A combination of linkage and association mapping strategies will be used to study the genetics of host-pathogen interactions. Linkage mapping is a robust genetic analysis method that has been widely applied in plant and fungal genetic research. Association mapping is a novel gene mapping approach used extensively in human and animal genetic research. These studies will provide insight into the genetic basis of virulence and pathogenicity of a necrotrophic pathogen, and identify and characterize resistance genes in the host. This information will advance scientific knowledge in this discipline and has applications in breeding of disease resistant crops.