title: The ectomycorrhizal status of a tropical black bolete, Phlebopus portentosus, assessed using mycorrhizal synthesis and isotopic analysis.
abstract: Phlebopus portentosus is one of the most popular wild edible mushrooms in Thailand and can produce sporocarps in the culture without a host plant. However, it is still unclear whether Phlebopus portentosus is a saprotrophic, parasitic, or ectomycorrhizal (ECM) fungus. In this study, Phlebopus portentosus sporocarps were collected from northern Thailand and identified based on morphological and molecular characteristics. We combined mycorrhizal synthesis and stable isotopic analysis to investigate the trophic status of this fungus. In a greenhouse experiment, ECM-like structures were observed in Pinus kesiya at 1 year after inoculation with fungal mycelium, and the association of Phlebopus portentosus and other plant species showed superficial growth over the root surface. Fungus-colonized root tips were described morphologically and colonization confirmed by molecular methods. In stable isotope measurements, the δ(13)C and δ(15)N of natural samples of Phlebopus portentosus differed from saprotrophic fungi. Based on the isotopic patterns of Phlebopus portentosus and its ability to form ECM-like structures in greenhouse experiments, we conclude that Phlebopus portentosus could be an ECM fungus.
authors.affiliation: Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai, 50200, Thailand.
authors.forename: Jaturong
authors.initials: J
authors.lastname: Kumla
authors.affiliation: Earth Systems Research Center, Morse Hall, University of New Hampshire, Durham, NH, 03824, USA.
authors.forename: Erik A
authors.initials: EA
authors.lastname: Hobbie
authors.affiliation: Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai, 50200, Thailand.
authors.forename: Nakarin
authors.initials: N
authors.lastname: Suwannarach
authors.affiliation: Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai, 50200, Thailand. saisamorn.l@cmu.ac.th.
authors.forename: Saisamorn
authors.initials: S
authors.lastname: Lumyong
mesh_terms: D000363:Agaricales / Q000145:classification / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification; D001487:Basidiomycota / Q000737:chemistry / Q000235:genetics / Q000254:growth & development* / Q000302:isolation & purification; D002247:Carbon Isotopes / Q000032:analysis / Q000378:metabolism; D025282:Mycelium / Q000737:chemistry / Q000254:growth & development* / Q000302:isolation & purification / Q000378:metabolism; D038821:Mycorrhizae / Q000737:chemistry / Q000235:genetics / Q000254:growth & development* / Q000302:isolation & purification; D009587:Nitrogen Isotopes / Q000032:analysis / Q000378:metabolism; D018517:Plant Roots / Q000382:microbiology; D013785:Thailand
chemical_list: D002247:Carbon Isotopes; D009587:Nitrogen Isotopes
keywords: Edible bolete; Mycorrhizal synthesis; Stable isotope; Trophic status