Fungi of the Fortuna Forest Reserve: Taxonomy and ecology with emphasis on ectomycorrhizal communities

Abstract

Panamanian montane forests harbor a high diversity of fungi, particularly of ectomycorrhizal (ECM) fungi, however their taxonomy and diversity patterns remain for the most part unexplored. Here we present state of the art fungal taxonomy and diversity patterns at Fortuna Forest Reserve based on morphological and molecular identification of over 1,000 fruiting body collections of macromycetes made over a period of five years. We compare these new results with previously published work based on environmental sampling of Oreomunnea mexicana root tips. We compiled a preliminary list of species and report 22 new genera and 29 new fungal species for Panama. Based on fruiting body collection data we compare the species composition of ECM fungal communities associated with Oreomunnea stands across sites differing in soil fertility and amount of rainfall. We also examine the effect of a long-term nitrogen addition treatment on the fruiting body production of ECM fungi. Finally, we discuss the biogeographic importance of Panama collections which fill in the knowledge gap of ECM fungal records between Costa Rica and Colombia. Given that the isthmus of Panama was an important migration route of ECM tree and fungal species from northern temperate areas to South America, the ECM fungal communities of Panama might show a high degree of isolation and therefore a high level of endemism. We expect that the forests at Fortuna will continue to yield new ECM macromycete data as we continue to study the collected specimens and describe new species.