Ecological and Genetic Variation Among Populations of <em>Boechera caeruleamontana</em> sp. nov. (Brassicaceae) from Blue Mountain and Dinosaur National Monumentin Eastern Utah and Western Colorado

• Main Author: Snyder, Melissa
• Format: Others
• Published: BYU ScholarsArchive 2017
• Subjects: Boechera; Brassicaceae; systematics; Dinosaur National Monument; plant ecology; conservation biology; genetic diversity; inbreeding; rare and endangered species; Plant Sciences
• Online Access: https://scholarsarchive.byu.edu/etd/6344; https://scholarsarchive.byu.edu/cgi/viewcontent.cgi?article=7344&amp;context=etd

Boechera is a large genus of flowering plants whose taxa are found primarily in North America. Boechera vivariensis (S.L. Welsh) W.A. Weber (the Park rockcress) is restricted to the Uintah Basin on Weber sandstone substrates in the vicinity of Dinosaur National Monument and Blue Mountain. The nomenclature of Park rockcress is significantly impacted by the discovery that the type collections of the taxon represent a rare, apomictic diploid resulting from the hybridization between B. thompsonii and an undescribed sexual diploid (to be called Boechera caeruleamontana sp. nov. Allphin and Windham). As a result, greater information is needed regarding how B. vivariensis and B. caeruleamontana. are distributed geographically in the region of Dinosaur National Monument and surrounding areas. Thus, we performed genetic analyses on leaf samples taken from over 50 individuals at known sites of B. vivariensis throughout its geographic range. Individuals from each site were also compared morphologically. We also compared associated plant communities at each site and characterized the soils. In our thorough sampling, we did not pick up B. vivariensis. All individuals sampled belonged to B. caeruleamontana, suggesting that most individuals previously assigned to B. vivariensis, are actually representative of B. caeruleamonanta. Populations of B. caeruleamontana were genetically diverse compared to other Boechera species, most likely indicative of its insect pollination strategy. However, all populations had lower heterozygosity than expected based upon Hardy-Weinberg expectations. Reproductive and genetic data indicated that populations are showing signs of inbreeding. The population at Jones Hole Fish Hatchery was most unique genetically, morphologically, and reproductively.