Origin and diversity of mushrooms in Eastern Canada and phylogenomics of selected groups

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Understanding the origin and distribution of biological diversity is fundamental to biology. The long-term goals of my research program are to investigate species richness and evolutionary relationships in the Agaricomycetes (Basidiomycota, Fungi) in a global scale, more particularly in the Agaricales. The latter includes the bulk of mushroom-forming fungi, and consists of about 10,000 species described worldwide, although many more probably exist. Several problems affect our estimates of fungal diversity and species distribution both globally and locally, particularly: (1) the scarcity of comprehensive regional or national flora, (2) the lack of modern taxonomic treatment (monographs) for most groups, and (3) the existence of many morphologically similar (cryptic) species. To help fix each of these three problems I propose to conduct the following work in the next five years: (1) Completion of a compendium of eastern Canada mushrooms based on historical records from the literature, herbaria, and other collection data, in combination with > 1,000 well-documented collections from Ontario and Quebec that were made in the last ten years and DNA-barcoded in my lab with both ITS and LSU sequences. This will produce a first realistic assessment of mushroom diversity in eastern Canada, and also, in many cases, permit taxonomic revisions in a phylogenetic context. This latter work is very well suited for multiple small projects for undergraduate students.(2) Preparation of world monographs for Amanita sections Caesarea and Vaginateae and for the genus Ganoderma in a phylogenomic framework; this will permit to infer the origin(s) and taxonomy of the eastern Canadian species belonging to these groups. Each group contains about 120 known species, many of which being either already in my possession or readily available from various sources (except material from Africa). Preliminary data indicates that a combination of 5 genes (ITS, EF1-alpha, LSU, RPB1 and RPB2) does not fully resolve phylogenetic relationships.(3) Population genomic studies and detection of cryptic species within the Amanita jacksonii species complex in North America. This species group of edible, ectomycorrhizal fungi is thought to consist of 4-5 species, but species delimitation is unclear. Members of this group are widespread in the southern U.S. and along the Appalaches. In Canada, A. jacksonii has been reported from few localities in southern Quebec, and has only been discovered recently in southern Ontario. I propose to compare whole genome sequences of at least 60 collections reprsentative of populations across the whole geographic and ecological range of this species group. To date, we have completed and annotated the genomes of two strains (one from Ontario, and one from Mexico); also, de novo collecting of fresh material is underway. This study should resolve species recognition within this species complex and shed light into speciation processes in mushrooms.