Hyphae and conidia of Microdochium bolleyi at 200x.
Photo Credit: Aaron David.

Microdochium bolleyi is a fungus commonly found living endophytically within plant roots, particularly those in grasses (Mandyam et al. 2010). The strain of M. bolleyi sequenced for the 1000 Fungal Genome Project was found growing within roots of three species of beachgrass along the USA Pacific Northwest Coast: the native Elymus mollis and the invasive Ammophila arenaria and A. breviligulata. The particular isolate (J235TASD1) sequenced was isolated from A. breviligulata. In a survey of beachgrass endophytes, M. bolleyi was the most frequently isolated endophyte (David et al. 2015a). M. bolleyi was also the fastest growing and one of the highest conidia-producing endophyte species in culture (David et al. 2015a).

While the effects of M. bolleyi on its beachgrass hosts has not yet been quantified, M. bolleyi is typically regarded as a commensal or weak pathogen (Kirk and Deacon 1987).

This particular strain of M. bolleyi is important for our understanding of how fungi tolerate extreme environments. Dune systems are characterized by high winds, low soil moisture, and low soil nutrients (Cooper 1958, David et al. 2015b), making them harsh environments for most organisms. Studying the genomes of species that thrive in these habitats may reveal how these species evolved traits for tolerating these environments.

References:

• Cooper WS. 1958. Coastal sand dunes. Boulder, Coliorado: Geological Society of America, Memoir 72.
• David AS, Seabloom EW, May G. 2015a. Plant Host Species and Geographic Distance Affect the Structure of Aboveground Fungal Symbiont Communities, and Environmental Filtering Affects Belowground Communities in a Coastal Dune Ecosystem. Microb Ecol. doi:10.1007/s00248-015-0712-6.
• David AS, Zarnetske PL, Hacker SD, Ruggiero P, Biel RG, Seabloom EW. 2015b. Invasive Congeners Differ in Successional Impacts across Space and Time. PLoS One. 10:e0117283, doi:10.1371/journal.pone.0117283.
• Kirk JJ, Deacon JW. 1987. Control of the take-all fungus by Microdochium bolleyi, and interactions involving M. bolleyi, Phialophora graminicola and Periconia macrospinosa on cereal roots. Plant Soil. 98:231–237, doi:10.1007/BF02374826.
• Mandyam K, Loughin T, Jumpponen  A. 2010. Isolation and morphological and metabolic characterization of common endophytes in annually burned tallgrass prairie. Mycologia. 102:813–821, doi:10.3852/09-212.
  Mandyam KG, Roe J, Jumpponen A. 2013. Arabidopsis thaliana model system reveals a continuum of responses to root endophyte colonization. Fungal Biol. 117:250–60, doi:10.1016/j.funbio.2013.02.001.