Phylogenetic diversity of true Morels (Morchella) in native Patagonian forests of Argentina.

PILDAIN M.B., ; VISNOVSKY S.; BARROETAVEÑA C.

La Antigua,

Workshop; 7th International Workshop on Edible Mycorrhizal Mushrooms; 2013

Universidad de San Carlos de Guatemala,

Conferenciesta en simposio Morchella is certainly one of the edible fungi with higher price and demand in world markets. However the identification at species level remains problematic due to their complex life cycles, minor differences and plasticity of morphological characters between species, combined with lack of agreement between scientific and common names. In Patagonia Argentina "Morel" species are mainly associated with native forests of Astrocedrus chilensis (mountain cypress) and Nothofagus antarctica (ñire) and very little is known about their taxonomy and phylogenetic relationships with other species in the same genus. The stated objective is the genetic characterization of a collection of Morchella isolates from Patagonia, establishing their phylogenetic relationships with other species of Morchella. DNA sequences were obtained from the 2 nuc-DNA regions more used in Morchella phylogeny, the nuclear ribosomal internal transcribed spacer region (ITS) and partial RNA polymerase I (RPB1). Individual and combined data sets analyses revealed that Patagonian morels belong to Elata clade and are grouped in three lineages strongly supported. Lineage "mountain blond morel" formed a cluster that includes isolates from Patagonia and representatives of M. frustrata corresponding to Mel-2 phylogenetic species from USA and Canada. Lineage ?fire adapted?, included isolates from Patagonia, together with isolates of the phylogenetic species Mel-7 from USA that were identified as M. septimelata, and collected from burned native forest, mainly composed by Austrocedrus chilensis and Nothofagus antartica. The phylogenetic analyses also showed that the species-rich Elata Subclade also includes Patagonian isolates, nested with Mel-18 and Mel-30 phylogenetic species from Dominican Republic and Turkey respectively. One remarkable biogeographic pattern concerns the placement of South American morels with North American taxa. Considering Patagonia resulted the region with lowest species richness reported until now, along with the evidence that Morchella is originated in western North America and that Patagonian isolates show morphological similarities with North American lineages, it is likely that these three lineages colonized South America from North America.