Submitted to: Fungal Genetics and Biology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 9, 2010
Publication Date: July 1, 2010
Citation: Taskin, H., Buyukalaca, S., Dogan, H.H., Rehner, S.A., O Donnell, K. 2010. A multigene molecular phylogenetic assessment of true morels (Morchella) in turkey. Fungal Genetics and Biology. 47(8):672-682. Interpretive Summary: Species of true morels (Morchella spp.) are one of the most highly prized edible fungi collected during the Spring in temperate regions of the Northern hemisphere. With their ever-increasing popularity, harvest of wild morels has become a commercially successful cottage industry in morel-rich regions of countries such as China, India, Mexico, Turkey and the United States. Although export of dried morels from Turkey quadrupled over the past five years, nothing is known about their genetic diversity. However, understanding their species diversity is critical to elucidating their ecology and systematics, and for formulating sound conservation policies to ensure sustainability of morel harvests. Towards this end, 247 specimens of Morchella, collected in the spring of 2007 and 2008 primarily in Mediterranean and Aegean providences of Southern Turkey, were analyzed phylogenetically using DNA sequence data from portions of two nuclear genes. Based on the result of this genetic screen, 62 collections chosen to represent the full range of genetic diversity were analyzed further using sequences from two additional nuclear genes. The results indicate that 15 phylogenetically distinct species of Morchella are present in Turkey, including 8 which are novel and potentially endemic. By way of contrast, four species representing one-third of the collections appeared to have been introduced from western North America. The results of this study will be interest to and benefit agricultural scientists and conservation biologists interested in the sustainability of morel harvests.
Technical Abstract: A collection of 247 true morels (Morchella spp.) primarily from the Mediterranean and Aegean Regions of Southern Turkey, were analyzed for species diversity using partial RNA polymerase I (RPB1) and nuclear ribosomal large subunit (LSU) rDNA gene sequences. Based on the result of this initial screen, 62 collections representing the full range of genetic diversity sampled were subjected to multigene phylogenetic species recognition based on genealogical concordance. The 62-taxon dataset consisted of partial sequences from three nuclear protein-coding genes, RNA polymerase I (RPB1), RNA polymerase II (RPB2), translation elongation factor (EF1-a), and partial LSU rDNA gene sequences. In addition, nuclear ribosomal internal transcribed spacer (ITS) rDNA sequences were generated for 36 terminals within the 62-taxon dataset for a subclade informally designated the Morchella elata species complex (MESC). Phylogenetic analyses of the individual and combined datasets, using maximum parsimony (MP) and maximum likelihood (ML), yielded nearly fully resolved phylogenies that were highly concordant topologically. GCPSR analysis of the 62-taxon dataset resolved 15 putative phylogenetically distinct species. The early diverging Elata (black morels) and Esculenta (yellow morels) clades were represented, respectively, by 13 and 2 species. Because a Latin binomial can be applied with confidence to only one of the 15 species (i.e., M. semilibera), species were identified by clade (Mel for Elata and Mes for Esculenta) followed by a unique Arabic number for each species within these two clades. Eight of the species within the Elata clade appear to be novel, including all seven species within the MESC and its sister designated Mel-25. Four of the Elata clade species (Mel-2, Mel-8, Mel-9 and Mel-10) representing one-third of the collections (88 of 265) appear to have been introduced inadvertently, possibly with the importation of forestry trees native to the Pacific Northwest of the United States. Results of the present study provide essential data for ensuring the sustainability of morel harvests through the formulation of sound conservation policies.