LE3 .A278 2019

2019

Walker, Allison

Acadia University

Bachelor of Science

Honours

Biology

Biology

Marine fungi contribute to nutrient cycling as major decomposers of organic matter in marine environments. Many species of marine fungi await discovery. In 2017, S. Adams at Acadia University (Walker Mycology Laboratory) isolated a new species of Lulworthia, an obligate marine ascomycete fungus in family Lulworthiaceae, from recently exposed intertidal wood from Apple River, Nova Scotia. This project focused on genetic characterization using rDNA as well as morphological characterization (macro-and micromorphology) of this new species. The fungus was cultured in the laboratory and DNA was extracted and amplified using ITS, 18S and 28S rDNA primers. Once samples were verified using gel electrophoresis, they were sent to Genome Québec for Sanger DNA sequencing. Separate phylogenetic trees of the sequences and closely related sequences downloaded from GenBank were made using the neighbor-joining method and 1000 bootstrap replicates with MEGA7 software program for the 3 gene regions. Phylogenetic analyses placed the new species on a separate branch with 92% bootstrap support, sister to Lulworthia atlantica, providing multilocus genetic evidence that it is a new species of marine fungus, provisionally named Lulworthia fundyense. As mature ascomata were not observed after more than 300 days of laboratory incubation, ascospores (sexual spores) were not observed. Chlamydospores and conidia were documented in culture. L. nom. prov. fundyense grew faster at warmer temperatures, 25 mm at 21C after 2 weeks on CMA 50% SW and minimal to no growth at 4C after 2 weeks; the fungus is now being tested for its ability to degrade crude oil to identify biotechnological potential and develop new strategies to reduce marine pollution. This project emphasized the ecological importance xviii of marine fungi, the undescribed diversity of marine fungi in cold water habitats and the need for further research on these enigmatic organisms.

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https://scholar.acadiau.ca/islandora/object/theses:3259