Assessing Genetic Diversity and Population Structure in the Imperiled Aconitum reclinatum (white monkshood), an Endemic Wildflower of Central Appalachia

Abstract

Aconitum reclinatum, white monkshood (Ranunculaceae), is a Pennsylvania critically imperiled plant species found in five states of the Appalachian region of the United States: Pennsylvania, West Virginia, Virginia, North Carolina, and Tennessee. This plant is adapted to cool, moist environments but faces threats from increasing habitat loss, deer browse, logging, and changes in rainfall and temperature associated with climate change. Comprehensive knowledge of A. reclinatum genetic population structure remains limited. To address this, we collaborated with Natural Heritage programs within the range of A. reclinatum to sample populations across the species distribution and generate a genotyping-by-sequencing data set of single-nucleotide polymorphisms (SNPs). This dataset was used to calculate population statistics (heterozygosity, inbreeding coefficient, fixation index) and infer population health and structure by conducting a Principal Component Analysis (PCA), spare non-negative matrix factorization (sNMF) analysis, and testing for a correlation between geographic and genetic distance. Our findings suggest strong genetic structure among populations of A. reclinatum and genetic isolation between populations. Natural Heritage programs should continue efforts to maintain populations and initiate further efforts for some populations that are experiencing lower genetic health. Additionally, genetic rescue may be required for some populations, although compatibility should be tested before it is implemented