Plant root - fungal pathogen interactions

植物根提供与土壤或生长基质的重要联系，确保养分和水分的吸收和传导。许多胁迫会减少根的生长，从而对植物的生长和发育产生负面影响。病原真菌会严重危害根的生长。这些栖息在土壤中的生物穿透根部，通过产生酶和毒素导致死亡(致病)。了解影响真菌致病的因素，以及植物如何通过产生防御化合物潜在地防御感染，将提供有价值的信息。产生的信息可用于减少这些真菌对食品生产的负面影响。在这项研究中，将从三个重要方面研究真菌×植物×环境的相互作用，以了解其发病机制。1)。转基因表达如何影响胡萝卜组织的防御反应和真菌致病？我们将评估编码过氧化物酶、NPR1(一种信号通路调节剂)和类胡萝卜素的基因对组织中不同分子、生化和细胞反应的影响。将测定PR-蛋白质、活性氧种和过氧化氢的水平，以及木质素的形成。这将有助于确定根部对病原菌攻击的关键防御反应。2)。发病机制能否通过dsRNA(霉菌病毒)感染来介导？已知双链RNA元件会影响真菌的毒力。将研究dsRNA在胡萝卜上查拉拉线虫致病中的作用，包括对毒力、真菌基因表达以及含有和不含有特定dsRNA元件的菌株表型的影响。这应该有助于确定与致病性有关的关键真菌参数。3)。铁是如何影响胡萝卜真菌致病的？虽然铁是植物生长和某些真菌生长所必需的微量营养素，但对真菌侵染根部的影响还没有得到很好的研究。铁对真菌酶的产生、寄主防御化合物的产生以及致病机理的影响，将以一种重要的根侵染病原菌Chalara elegans为例进行研究。建议的研究将为深入了解植物根-真菌病原菌相互作用提供有价值的见解，并提供新的信息。

Plant roots provide a vital connection with the soil or growth substrate, ensuring uptake and conductance of nutrients and water. Many stresses reduce root growth, which negatively impacts plant growth and development. Pathogenic fungi can severely compromise root growth. These soil-inhabiting organisms penetrate roots, causing death through production of enzymes and toxins (pathogenesis). Knowledge of the factors affecting fungal pathogenesis and how plants can potentially defend against infection, via production of defense compounds, would provide valuable information. The information generated can be applied to reduce the negative impact of these fungi on food production. In this research, three important aspects of fungal x plant x environment interactions will be studied to understand pathogenesis. 1). How does transgene expression affect defense responses in carrot tissues and fungal pathogenesis ? We will evaluate effects of genes encoding peroxidase, NPR1 ( a signaling pathway modulator ) and carotenoids on different molecular, biochemical, and cellular responses in tissues. The levels of PR-proteins, active oxygen species and hydrogen peroxide, as well as lignin formation, will be determined. This will help identify the key defense responses in roots to pathogen challenge. 2). Can pathogenesis be mediated through dsRNA (mycovirus) infection ? Double-stranded RNA elements are known to affect fungal virulence. The effects of dsRNA on pathogenesis of Chalara elegans on carrot will be investigated, including the effects on virulence, fungal gene expression, and phenotype of strains with and without specific dsRNA elements. This should help identify the key fungal parameters involved in pathogenicity. 3). How does iron affect fungal pathogenesis on carrot ? While iron is an essential micronutrient for plant growth and for some fungi, effects on root infection by fungi have not been well researched. The effect of iron on fungal enzyme production, production of host defense compounds, and on pathogenesis, will be studied using Chalara elegans, an important root-infecting pathogen. The proposed research will provide valuable insight into plant root-fungal pathogen interactions and provide novel information.