Diversity and function of fungal root endophytes in Canadian boreal forests

植物的根被各种各样的真菌所定殖。这些不仅包括有害的病原体，还包括促进植物生长的有益物种。还有一些作为植物根组织内的“内生菌”存在，其不引起疾病症状或形成通常在有益的关联中发现的结构。根内生真菌在植物中的数量非常丰富，但其隐蔽性限制了对它们在土壤生态学中作用的研究。根内生真菌潜在地代表了生物多样性的一个未被发现的来源。不仅以前的研究发现真菌根内生菌的多样性高水平，但内生真菌的叶子（地上类比）被认为是“超多样性”。现代的DNA检测技术比以前使用的技术灵敏得多，应该能揭示这些看不见的生物的真实多样性。真菌根内生菌的功能也知之甚少。有些物种是“潜伏病原体”，最终会引起疾病症状。另一些则可能与宿主建立有益的关系，因为它们可能会回报植物“服务”。这可能是以保护免受有害土壤生物或改善植物养分吸收的形式。根内生真菌还可以将树木的根部与生长在其林下的植物的根部连接起来，从而使它们的利益得以分享。拟议研究的主要目标是提高我们对根内生真菌的多样性和功能的理解。这项工作将专门针对北方森林树木的真菌根内生菌，由于高内生菌多样性和植物间连接的潜力。所收集的信息将使我们进一步了解对北方森林的健康至关重要的基本地下过程，并应引起森林生态学家和管理人员的兴趣。在整个时间范围内，拟议的研究将聘请两名研究生和五名本科生研究助理在工作的各个方面，包括数据分析，会议演示和出版机会。

Plant roots are colonized by a diverse array of fungi. These include not only detrimental pathogens, but also beneficial species which improve plant growth. Still others exist as "endophytes" within the plant root tissue, which do not cause disease symptoms or form the structures normally found in beneficial associations. Root endophytic fungi are often abundant and found on almost all plants so far studied, yet their cryptic nature has constrained investigation into their role in the ecology of the soil environment. Root endophytic fungi potentially represent an undiscovered source of biodiversity. Not only have previous studies of fungal root endophytes uncovered high levels of diversity, but the endophytic fungi of leaves (the above-ground analogy) are thought to be "hyperdiverse". Modern DNA based detection techniques are far more sensitive than those previously employed, and should reveal the true diversity of these unseen organisms.The function of fungal root endophytes is also poorly understood. Some species are "latent pathogens" which will eventually elicit disease symptoms. Others are likely to be involved in beneficial relationships with their hosts in that they may return a "service" to the plant. This may be in the form of protection against detrimental soil organisms or improvement of plant nutrient uptake. Fungal root endophytes may also connect the roots of trees to the roots of plants growing in their understories, allowing for their benefits to be shared.The main objective of the proposed research is to improve our understanding of the diversity and function of the root endophytic fungi. The work will specifically target fungal root endophytes of boreal forest trees, due to the potential for high endophyte diversity and inter-plant connections. The information gathered will further our understanding of fundamental below-ground processes critical to the health of the boreal forest and should be of interest to forest ecologists and managers. Throughout its timeframe, the proposed research will engage two graduate and five undergraduate student research assistants in all aspects of the work, including data analyses, conference presentations and publication opportunities.