LE3 .A278 2019

2019

Walker, Allison

Acadia University

Bachelor of Science

Honours

Environmental Science

Earth & Environmental Sciences

Crocanthemum canadense (L.) Britt. (Cistaceae) is a small, herbaceous plant that is critically imperiled in Nova Scotia. Habitat loss and an insect pest, Mompha capella (Momphidae), are contributing to population decline. The role of fungal associations in C. canadense populations is unknown, and thus the primary goal of this research was to identify fungal symbionts to aid in propagation and conservation strategies. Fungi were isolated from the roots, stems, and leaves of C. canadense plants collected throughout six sites at 14 Wing Canadian Forces Base Greenwood, Nova Scotia. Arbuscular mycorrhizal fungi (AMF) were observed using root staining and microscopic techniques to determine percent root colonization. Site 3 had the highest average A MF colonization rate (53%; n = 3). Using ITS rDNA barcoding, 43 fungal species were identified from roots, 14 from leaves, 6 from upper stems, and 11 from lower stems. Six ascomycete fungi occurred in more than half of the study sites and colonized more than a third of the plants sampled. These included Pyrenophora tetrarrhenae colonizing 89% of plants which was isolated from above-ground tissues, Arcopilus aureus (56%; from all tissue types), Pilidium concavum (50%; from roots, leaves, and lower stems), Phialocephala cf. fortinii (44%; from roots and lower stems), Apiognomonia cf. hystrix (39%; from all tissue types), and Sphaeronaemella fragariae (39%; only from leaves). Apiognomonia cf. hystrix and P. tetrarrhenae were present in C. canadense tissue at all six sites. This research provides the first report of the fungal relationships potentially influencing endangered Nova Scotia C. canadense populations and could be used to enhance the success of future plant propagation and conservation efforts.

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https://scholar.acadiau.ca/islandora/object/theses:3308