Exploring the Genome of Glomeromycotan Fungi -- Molecular Approaches to Arbuscular Mycorrhiza Functioning -- The Interface Between Plants and Mycorrhizal Fungi: Nutrient Exchange, Signaling and Cell Organization -- Arbuscular Mycorrhiza -- a Key Component of Sustainable Plant--Soil Ecosystems -- The Geosiphon--Nostoc Endosymbiosis and its Role as a Model for Arbuscular Mycorrhiza Research -- De-Constructing a Mutualist: How the Molecular Blueprints of Model Symbiotic Fungi are Changing our Understanding of Mutualism -- Carbohydrates Exchange Between Symbionts in Ectomycorrhizas -- Lipids of Mycorrhizas -- The Role of the Stonesphere for the Interactions between Mycorrhizal Fungi and Mycorrhizosphere Bacteria during Mineral Weathering -- Context-Dependent Interaction Hierarchies and the Organization of Ectomycorrhizal Fungal Communities -- Ectendomycorrhizas: Occurrence, Structural Characteristics, and Possible Roles -- Orchid Mycorrhizas: Molecular Ecology, Physiology, Evolution and Conservation Aspects -- The Symbiotic Fungus Piriformospora indica: Review -- Genetic Diversity and Functional Aspects of Ericoid Mycorrhizal Fungi -- The Symbiotic Phenotype of Lichen-Forming Ascomycetes and Their Endo- and Epibionts -- Basidiolichens -- Bacteria and the Lichen Symbiosis -- Fungal and Bacterial Volatile Organic Compounds: an Overview and Their Role as Ecological Signaling Agents.