Fungal communities associated with energy crop residues exhibit high alpha and beta diversity and are readily cultured

Fungi are vital to terrestrial ecosystems as plant mutualists, pathogens, and decomposers.  Similar to other microbes, little is known about beta diversity amongst fungal communities. Additionally, comparisons between culture and high-throughput sequence analyses generally result in different sets of species suggesting culture or amplification biases strongly affect the sampling.  Our goals were: 1) to determine beta diversity across varying physical distances in fungi associated with two energy crops, Miscanthus and sugarcane, via culture-independent methods and 2) to compare a previous study’s culture approach to our analysis. We collected 16 plant detritus samples per site in a spatially explicit manner from seven Miscanthus sites in Illinois and ten sugarcane sites in Louisiana. DNA was extracted from freeze-dried material, and the fungal ribosomal internal transcribed spacer region was amplified and pyrosequenced to acquire amplicon sequences.  We used QIIME to assign operational taxonomic units (OTUs) and mantel tests to compare community compositional change with distance. Preliminary results show high alpha diversity and a significant increase in community dissimilarity at all spatial scales for both Miscanthus and sugarcane. The ten most frequent OTUs were also found among the cultured isolates.  These results show that fungal species vary even within short distances in relatively uniform habitats, and contrary to most microbial systems, the dominant players in these communities are readily culturable.  Many of these fungi are useful for converting plant material into biofuels, and knowledge of the spatial patterning of their taxonomic diversity may allow for better-designed bioprospecting schemes to retrieve functional diversity.