Study of fungi with endophytic and mycoparasitic lifestyles for their multiple effects on host traits

随着全球变暖，植物面临着越来越大的干旱和疾病压力。了解植物共生菌如何提高植物的抗性，对于维持植物的多样性和可持续的作物生产至关重要。每一进化的植物群体都通过容纳真菌共生体来适应，真菌共生体是由有益的内生菌和寄生真菌组成的联合体，驻留在植物组织中。它们形成了植物的第二基因组，是种子韧性和萌发的主要积极贡献者之一，种子萌发是植物生命周期和适应性的关键阶段。我的项目已经确立了自己在这一研究领域的领先地位，领导发现真菌生命力(Vitalitas=‘生命力’)就证明了这一点，它定义了植物在真菌营养(trohe=‘营养学’)的连续统一体中的表现。在小麦(Triticaceae)中，真菌活力(内生植物-种子联合)诱导Colorhiza驱动的种子层积和植物激素生物合成基因的特异性表达，从而实现改善发芽/出苗和抗逆性。这一概念引起了全球粮食安全行业的极大兴趣；然而，一些科学问题仍有待回答，包括：(A)在植物-真菌共同进化的过程中，植物如何选择不同的、特定于基因组的种子内共生体？以及(B)内生接种剂如何操纵植物微生物群，从而控制植物的行为适应和进化途径？将植物微生物群作为一个系统进行研究需要荟萃组学和比较研究，以揭示植物-内生菌共生的灰色区域。在本项目中，将结合MiSeq下一代测序(NGS)技术来研究内共生菌的元基因组学。然后，NGS将与qPCR/微阵列、共聚焦显微镜、FTIR光谱和LC/MSMS分析方法相结合，以阐明植物微生物组和代谢组对非生物和生物胁迫的响应。定量测定不同寄主类型山羊草种子组织中的代谢变化对于了解内生作用对种子萌发的影响至关重要。绘制关键功能基因在植物表型间的表达图谱将有助于阐明内共生菌改善寄主性状的机制，以及进化对逆境耐受性的影响。此外，定义谷物进化差异的多倍化事件将是解释共同进化的关键。利用组学技术比较谷类和拟南芥的功能种子组织，可以确定植物个体发育中与内生共生相关的特定表型变化。总体目标是产生关于内生共生的基础知识，以便更好地了解植物的进化特征，从而创造出一种提高作物抗逆性和生产力的工具。

With global warming, plants face increasing stress from drought and disease. Understanding how plant mycosymbionts (myks='fungus', sumbiosis='mutualism') improve plant resistance is critical for maintaining plant diversity, and sustainable crop production. Each evolutionary group of plants adapts by harboring mycosymbionts, a consortia of beneficial endophytes and mycoparasites residing within plant tissue. Forming the plant's 'second genome', they are among the main positive contributors to seed resilience and germination, a vital phase to a plant's lifecycle and adaptability. My program has established itself as a leader in this research area, as evidenced by leading the discovery of mycovitality (vitalitas='vital force'), which defines plant performance in a continuum with mycotrophy (trophe='nutrition'). Mycovitality (endophyte-seed association) induces coleorhiza-driven seed stratification and specific expression of phytohormone biosynthesis genes to achieve both improved germination/seedling emergence and stress tolerance in wheat (Triticaceae). The concept has peaked the interest of the global food security industry; however, a number of scientific questions still remain to be answered including, (a) over the course of the plant-fungus co-evolution, how have plants selected distinct, genome-specific profiles of seed endosymbionts? and (b) how does the endophytic inoculant manipulate the plant microbiome, so as to control plant behavioral adaptations and evolutionary pathways? Investigating the plant microbiome as a system demands meta-omics and comparative studies to unravel gray areas of plant-endophyte symbiosis. In this project, a combination of MiSeq next generation sequencing (NGS) technology will be applied to study the metagenomics of endosymbionts. The NGS will then be coupled with qPCR/microarray, confocal microscopy, FTIR spectroscopy and LC/MSMS analytical methods to elucidate plant's microbiome and metabolome responses to abiotic and biotic stresses. Quantifying metabolic shift in the seed tissues of Aegilops-Triticum host genotypes is essential for understanding endophytism's effect on seed germination. Mapping the expression of key functional genes across plant phenotypes will aid in elucidating the mechanisms by which endosymbionts improve host traits, with evolutionary effects on stress tolerance. Moreover, polyploidization events, which define the evolutionary divergence of cereals, will be key in explaining co-evolution. Comparing functional seed tissues of cereals' with those of Arabidopsis' using -omics techniques would identify specific phenotypical changes in the plant's ontogeny related to endosymbiosis. The overall goal is to generate fundamental knowledge on endosymbiosis so as to better understand plant evolutionary traits, thus creating a tool for improved crop stress resilience and productivity.