Research Initiation Award: Unraveling Genetic and Environmental Constraints to Adaptation in Rare Plant Species

The Historically Black Colleges and Universities Undergraduate Program (HBCU-UP) through Research Initiation Awards (RIA) provide support for junior and mid-career faculty at Historically Black Colleges and Universities who are building new research programs or redirecting and rebuilding existing research programs. It is expected that the award will help to further the faculty member's research capability and effectiveness and improve research and teaching at the home institution. This award will advance understanding of the role of genetic and environmental pressure on rare plant adaptation, train undergraduates in genomics research, and enhance research capacity at Spelman College. Rare plant species contribute to the important variations in plant life, stable ecological communities, and ecosystem functions that support human well-being. However, small populations and restricted geographic distributions can make rare plants especially vulnerable to environmental change, habitat alteration, and loss of genetic variation. The project will investigate how past population changes and fine-scale environmental conditions influence the persistence of Ribes echinellum, a federally threatened shrub found in only two known locations. Research will focus on the South Carolina population, where plants occur across a small area containing distinct core and edge habitats. The project will determine whether plants in different parts of the population differ in genetic variety, inbreeding, environmental conditions, flowering, survival, and growth. Results will help identify environmental and genetic factors that may limit persistence and adaptation. Findings will directly support conservation planning by the Atlanta Botanical Garden and will be shared with government agencies and conservation organizations responsible for rare plant monitoring, habitat management, propagation, restoration, and translocation. Spelman College students will participate in research, visit collaborating laboratories, and communicate findings to scientific, conservation, and public audiences. The project will strengthen partnerships among Spelman College, the Atlanta Botanical Garden, Cornell University, government agencies, and conservation organizations while preparing undergraduate students for careers in science. The project will characterize demographic history, genetic structure, genetic variety, inbreeding, effective population size, individual performance, and functional genomic variation within the South Carolina population of Ribes echinellum. A functionally annotated reference genome and whole genome resequencing data from 148 focal plants will support analyses of historical population change, genetic differentiation between core and edge habitats, genetic variety, inbreeding, and genomic regions potentially influenced by selection. Environmental data loggers and soil measurements will quantify fine-scale variation in temperature, soil moisture, soil nutrients, and acidity near the same focal plants. Repeated measurements of plant size and flowering will test associations between environmental variation and individual performance. A reciprocal transplant experiment using greenhouse-propagated cuttings from core and edge plants will evaluate how plant origin and growing environment influence survival and growth. Statistical analyses will also test whether environmental variation is associated with variation in functional genomic regions while accounting for geographic distance and population structure. Integration of genomic, environmental, observational, and experimental data will clarify how demographic history and microclimate shape adaptive potential within a rare plant population. Project outcomes will provide a scientific basis for conservation management of Ribes echinellum, advance understanding more generally of rare species with similar distributions and demographic histories, expand public engagement with conservation science, and provide research training for undergraduate students at Spelman College. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.