In vivo root colonisation pattern and in vitro cultural aspects of Posidoniomyces atricolor. a In vivo colonisation on the root surface (arrows) and in the hypodermis (asterisks) of P. oceanica b DSE colonisation on the root surface c germinating microsclerotia stained with trypan blue (arrows) d compact colony developed from microsclerotia (arrow) e surface-sterilised root segments yielding P. atricolor compact colonies (black arrows), sometimes with substrate mycelium (white arrows) f compact colonial morphotype g mycelial colonial morphotype h mycelial morphotype developing from microsclerotia (arrows) in transversal section. Scale bars: 20 μm (a, b), 50 μm (c), 100 μm (d), 200 μm (f, h), 500 μm (g).