Cassidy Coker

Honors Undergraduate Research Scholar

Cassidy joined the lab in Fall 2019 as a TTU Honors College Undergraduate Research Scholar. She has worked on two projects in the lab:

Characterization of the Fungal Microbiome in 50-Year-Old Plant Herbarium Specimens

Can we characterize the fungal microbiome of the past using plant herbarium specimens? For this project, Cassidy extracted DNA from leaf and root tissue of 50-year-old herbarium specimens, and amplified the internal transcribed spacer (ITS). Cassidy presented this research in a “lightning talk” at the 2020 Botany Conference (held virtually).

Elemental and Isotopic Analysis in 50-Year-Old Herbarium Specimens

This research project focuses on sampling herbarium specimens within the GUMO collection to observe the disparity in foliar nitrogen concentration per unit area, water usage, and stomatal density. Cassidy collected tissue from more than 200 herbarium specimens, including species of grasses, forbs, and ferns. Using mass spectroscopy, both nitrogen concentration per unit area and isotopic carbon ratio were determined to assess how the plant’s metabolic activity was affected by its environment when it was alive 50 years ago. To determine the effects of location on plant composition, precise georeferencing coordinates and stomatal density were compared amongst species to observe the effects of elevation and habitat on leaf morphology and physiology.