REU: Reciprocal Relationships of Distant Sagebrush Communities with Their Mycorrhizal Fungi

三叶蒿（Artemisia tridentata）是北美地区分布最广泛的灌木，在许多群落中具有地方优势，部分原因是由于生理和遗传特性。我们将研究三叉草与其菌根真菌群落的关系，以确定内生真菌-寄主关系的局部适应是否在三叉草的广泛分布中起作用。这些事实对这种关系具有特别的意义。菌根感染后，灌木生物量增加2.5倍。菌根真菌的伴生种在南部地区为热带起源，在北部地区为温带起源。不同种类的菌根真菌对这种寄主有不同的生理作用，因此当地真菌群落可能解释了灌木的成功。将采取描述性和功能性的方法，包括对三叉戟林分中囊状-丛枝菌根真菌群落的检查，以及在南加州和怀俄明州西南部的三叉戟及其相关真菌的相互移植。一个跨学科的研究团队将测量形态学、解剖学、生理学和真菌参数，以确定移植的成功。测量将使用概念层次模型进行集成。这些数据将用于整理不同地点、不同植物种群、不同真菌种群和属对三叉戟的本地适应性和在地理偏远地点的持续生存能力的差异。

Artemisia tridentata (sagebrush) is the most widely distributed shrub in North America and is the local dominant in many communities, due in part to physiological and genetic characteristics. The relationships of A. tridentata with its mycorrhizal fungal communities will be examined to determine if local adaptations of the endophyte-host relationship have a role in the wide distribution of the shrub. These facts are of special interest in this relationship. The shrub has up to a 2.5 times increase in biomass with mycorrhizal infection. Associated species of mycorrhizal fungi are of tropical origin in southern sites and of temperate origin in the northern sites. Different species of mycorrhizal fungi have different physiological effects on this host so local fungal communities may explain the success of the shrub. Both descriptive and functional approaches, including an examination of vesicular-arbuscular mycorrhizal fungal communities in stands of A. tridentata throughout its distribution and reciprocal transplants of A. tridentata and its associated fungi between sites in Southern California and Southwestern Wyoming, will be taken. An interdisciplinary team of researchers will measure morphological, anatomical, physiological, and fungal parameters to determine success of the transplants. The measurements will be integrated using a conceptual hierarchical model. These data will be used to sort out differences between sites, plant populations, and fungal populations and genera on local adaptations of A. tridentata and its ability to persist in geographically remote sites.