Local Adaptation of Blue Penstemon: Molecular and Morphological Characterizations of a Potential Restoration Species for the Northern Basin and Range and Snake River Plain

• Main Author: Stettler, Jason Mark
• Format: Text
• Language: unknown
• Published: BYU ScholarsArchive 2022
• Subjects: biogeography; adaptive radiation; chloroplast genome; plastome; phylogenetics; Penstemon cyaneus; common garden; seed production; Life Sciences; Arctic
• Online Access: https://scholarsarchive.byu.edu/etd/9431; https://scholarsarchive.byu.edu/context/etd/article/10440/viewcontent/6932516322022420160101_etd.pdf

Penstemon is one of North America's largest endemic genera with over 280 described species. These species are distributed throughout most of North America from the Arctic northern latitudes to tropics of Central America. The genus has historically been divided into six subgenera, but has recently been reorganized into two subgenera following some recent phylogenetic studies. I made a comprehensive assessment of the Penstemon genus' geographic distribution utilizing herbaria databases by ecoregion to discuss the general ecologic adaptations of each historic subgenera. I also assessed the Penstemon genus' bee pollinator diversity utilizing online databases of bee specimen collections associated with Penstemon flowers. I investigated the efficacy of utilizing the plastid genomes (plastomes) of 29 species in the Lamiales order, including five newly sequenced Penstemon plastomes, for analyzing phylogenetic relationships and resolving problematic clades. I compared whole-plastome based phylogenies to phylogenies based on individual gene sequences (matK, ndhF, psaA, psbA, rbcL, rpoC2, and rps2) and concatenated sequences. I found that my whole-plastome based phylogeny had higher nodal support than all other phylogenies, which suggests that it provides greater accuracy in describing the hierarchal relationships among taxa as compared to other methods. I found that the genus Penstemon forms a monophyletic clade sister to, but separate from, the Old World taxa of the Plantaginaceae family included in our study. My whole-plastome based phylogeny also supports the rearrangement of the Scrophulariaceae family and improves resolution of major clades and genera of the Lamiales. I evaluated 16 accessions of P. cyaneus with 14 accessions of closely related Penstemon species in common garden in two distinct environments in Aberdeen, ID and Provo, UT during 2018 and 2019. I evaluated the accessions for key commercial seed production traits including survival, plant height, number of stems, and seed production. Both common gardens ...