Volatiles in Communication of Agaricomycetes

Abstract

Much attention has been given in recent time to communication processes of fungi. Fungi communicate on all organismal levels, within an organism, within the species, with other fungal species, and with other kinds of organisms, both from prokaryotes and eukaryotes. Most of our current knowledge on fungal communication has been collected from Ascomycetes, while the relevance for Agaricomycetes in growth, development, and ecological success is increasingly been recognized. Signals are often volatile organic compounds (VOCs) which can reach receivers on short and longer distances through all elements, air, water, and soil. Fungal VOCs used as signals are of broad chemical nature. Eight-carbon compounds including 1-octen-3-ol as the typical mushroom odor are appointed by many species, in autoregulatory processes and manifold in positive and negative interactions with other organisms. In particular, the rich diversity of terpenoids produced by Agaricomycetes offers ample possibilities to establish species-specific signals defined by an individual compound or, more likely, by unique cocktails of VOCs. In this chapter, we present a comprehensive survey on communication activities of Agaricomycetes on all organismal scales and community levels in which fungal VOC-mediated signaling is recognized. Where information is available, biochemical natures of responsible VOCs are presented. Agaricomycetes send messages out in a fascinating wealth of occasions and purposes, such as for own growth and development, in organismal competitions for food and space, for defense, and for dispersal. With a fungal sender and a potential receiver, experimental research mostly still concentrates on just two players or in best cases a few participants when, e.g., eavesdroppers come into play. However, broader ecological contexts of communication processes of Agaricomycetes are emerging with effects not only for the individual sender of signals or its fungal species and its direct addressees but also for their specific ecological guilds, niches and habitats, and the broad diversity of organisms living in the shared environments.