Grass-Epichloë Interactions in Current and Future Climates

入侵物种正在重新定义生物地理学的经典边界，并影响生态系统的功能。它们是人类世的一个决定性特征。几种相关的欧洲原产草种在管理草原上具有全球意义。这些物种受到了密集的育种计划，并在温带世界的大部分地区大举销售。它们在北美和南美、澳大利亚、新西兰、非洲和亚洲部分地区都有种植。它们经常逃避种植，与本地物种激烈竞争，据称减少了生物多样性，损害了生态系统功能。这些草种的成功，无论是在栽培内部还是外部，都是由于它们与Epichloë属中有益的、无性的、垂直传播的内生真菌物种的进化历史。这些草真菌共生对农民来说是非常理想的，但会危及邻近的未管理的生态系统。面对持续剧烈的气候变化，一个悬而未决的问题是，这些共生是否会继续具有经济重要性和生态侵入性。我有四个近期目标。1. 建立微生物组、代谢组、蛋白质组和Epichloë浓度随温度和湿度变化的统计模型。2. 建立蚜虫食草动物种群动态与寄主植物微生物组、代谢组、蛋白质组、Epichloë浓度、温度和湿度之间关系的统计模型。3. 确定决定Epichloë感染在促进草类入侵中的作用的主要驱动变量。4. 创建蚜虫-草- Epichloë相互作用的生物学详细数学模型。我将通过一个长期的多地点实验来研究温度和降水对这种草-真菌内生菌相互作用的影响。这些站点位于从安大略省米尔顿开始到伊利诺伊州卡本代尔结束的800公里横断面上。该样带的生长期平均温度变化为12°C，生长期降水差异为246 mm。在生长季节的每个月，我将描述草的微生物组、蛋白质组、代谢组和Epichloë浓度。我还将描述在有Epichloë内生菌和没有Epichloë内生菌的情况下草的入侵性和食草性。最后，我将进一步发展我最近发表的草内生菌相互作用的数学模型，利用这项实验工作的细节。

Invasive species are redefining the classical boundaries of biogeography and affecting ecosystem functioning. They are a defining feature of the Anthropocene. Several related grass species of European origin are globally significant in managed grasslands. These species have been subjected to intensive breeding programs and marketed aggressively throughout much of the temperate world. They are cultivated throughout North and South America, Australia, New Zealand, Africa and parts of Asia. They routinely escape cultivation to compete aggressively with native species, purportedly reducing biodiversity and impairing ecosystem functioning. Much of the success of these grass species, both inside and outside of cultivation, is due to their evolutionary history with beneficial, asexual, vertically transmitted endophytic fungal species in the genus Epichloë. These grass-fungal symbioses are highly desirable to farmers but endanger neighbouring unmanaged ecosystems. In the face of dramatic ongoing climatic change, an open question is whether or not these symbioses will continue to be as economically important and ecologically invasive. I have four near-term objectives. 1. Create a statistical model of the microbiome, metabolome, proteome and Epichloë concentrations across years and within the growing season, as a function of temperature and moisture. 2. Create a statistical model of the relationship between aphid herbivores population dynamics as a function of the host plant's microbiome, metabolome, proteome, Epichloë concentrations, temperature and moisture. 3. Identify the main driving variables that determine the role of Epichloë infection in promoting the grasses's invasiveness. 4. Create a biologically detailed mathematical model of the aphid-grass- Epichloë interaction. I will accomplish these objectives using a long-term multi-site experiment to investigate the effects of temperature and precipitation on this grass-fungal endophyte interaction. These sites are located along an 800 km transect beginning in Milton, Ontario, and terminating in Carbondale, Illinois. This transect spans a 12°C change in average growing season temperature and 246 mm difference in growing season precipitation. Each month during the growing season I will characterize the grasses' microbiome, proteome, metabolome, and Epichloë concentrations. I will also characterize the grasses' invasiveness and herbivore resistance with and without the Epichloë endophyte. Finally, I will further develop a mathematical model of the grass-endophyte interaction that I recently published using details from this experimental work.