Symbiotic associations among fungi and plants play a fundamental role in the evolution and establishment of plants within terrestrial ecosystems. However,  our current knowledge of plant-associated fungal communities is very limited.  We have been performing a comprehensive inventory of grass-associated fungal communities at different scales: different plant organs, grass species, and ecosystems. Geographic distribution of root-associated communities at a transcontinental scale was studied within a single host: Bouteloua gracilis. We collected more than 3000 sequences from environmental samples using fungal-specific primers.
Results/Conclusions

Fungal communities associated with different plant organs for the same plant species were significantly different. Within a semiarid grassland ecosystems in New Mexico, dominant grass species shared a core group of root-associated  fungal communities with 90% of sequences representing the orders Pleosporales, Agaricales, and Sordariales. The two most common OTUs within the grasses (91 and 85 of 331 sequences) were related to Paraphaeospheria sp. and Moniliophthora sp., respectively. At a transcontinental level, fungal taxa within Pleosporales and Agaricales were found associated with roots at all study sites  but plants showed significant differences in the abundance of fungal taxa in the latitudinal gradient. Possible ecological roles of these symbionts, their diversity, and  biogeographical distributions will be discussed