CSI Botany: DNA Barcode “Fingerprints” Identify Cryptic Urban Flora

Author

Luis R. Vega, CUNY Lehman CollegeFollow

Date of Award

2023

Document Type

Thesis

Degree Name

Master of Science (MS)

Department

Biological Sciences

First Advisor

Jack Henning

Second Advisor

Joseph Rachlin

Third Advisor

Moira Sauane

Abstract

As short genomic markers, DNA barcodes can play a role in conservation by identifying cryptic species and hybrids when morphological approaches fall short. Here we present our application of barcodes to the identities of two wetland taxa as part of an ongoing floristic inventory of Van Cortlandt Park (VCP), Bronx, NY. Previous barcode data by Marriott et al. (2018) identified the VCP lake water lily as the exotic Nymphaea alba, rather than the native N. odorata as historically described. In addition, cattails in the park were historically identified as the native Typha latifolia and the exotic T. angustifolia, but display intermediate leaf widths and floral structure, suggesting the presence of the aggressively invasive hybrid, T. x glauca. Both the water lilies and cattails represent examples of possible hybridization and cryptic invasion. Since the NYC Department of Parks and Recreation maintains an active exotics removal campaign, clarifying the provenance of these taxa is essential for management of VCP’s biodiversity. Multiple samples were recorded morphologically and used for DNA extraction using a combination of plastid and nuclear barcodes: rbcL and ITS for the water lilies, and trnL-trnF, psbA-trnH, and ITS for the cattails. We initially compared our sequenced data marker-by-marker against published GenBank sequences before opting for a pooled approach using parsimony, maximum likelihood, and Bayesian inference to examine corroboration of resolution. The results of a morphological parsimony were compared against the molecular resolutions, requiring examination of the plants throughout the entire season since key distinguishing characters were not available at any one viewing. Our results confirmed the water lilies are the native N. odorata and the cattails are T. latifolia and T. angustifolia. There was weak molecular support that the VCP cattails are hybridizing. Applying DNA barcoding to efforts such as these may improve the ability of conservationists to meet biodiversity goals by providing increased confidence in the accurate identification of local species that might otherwise prove intractable to identify in the field without season-wide observations.

Recommended Citation

Vega, Luis R., "CSI Botany: DNA Barcode “Fingerprints” Identify Cryptic Urban Flora" (2023). CUNY Academic Works.
https://academicworks.cuny.edu/le_etds/34