Vegatative propagation preserves genomic diversity and informs translocation strategies in a rare clonal plant

Authors: MASSATTI, ROB - Consultant; BAINBRIDGE, SUSAN - Us Geological Survey (USGS); Copeland, Stella; CROUCH, CARTER - International Crane Foundation; FASKE, TREVOR - Consultant; Hamerlynck, Erik; PALMER, BRANDON - Oregon Desert Land Trust; ROYBAL, CARLA - Us Geological Survey (USGS)

Submitted to: Evolutionary Applications
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/24/2026
Publication Date: 7/18/2026
Citation: Massatti, R., Bainbridge, S., Copeland, S.M., Crouch, C., Faske, T.M., Hamerlynck, E.P., Palmer, B., Roybal, C. 2026. Vegatative propagation preserves genomic diversity and informs translocation strategies in a rare clonal plant. Evolutionary Applications. 2026;19:070299 1-13. https://doi.org/10.1111/eva.70299.
DOI: https://doi.org/10.1111/eva.70299

Interpretive Summary: Plant conservation and restoration efforts often involve introducing plants into sites with transplants. However, it is unclear whether this practice effectively maintains the genetic diversity within natural populations, which may be key for long-term persistence. We collected plants from natural populations and introduction sites for a rare, vegetatively reproducing wetland grass species in eastern Oregon. We found distinct genetic differences in the two existing natural population clusters and high degree of genetic similarity between introduced patches and their ‘parent’ natural populations. This suggests that outplanting efforts could preserve genetic diversity for similar species, such as other vegetatively reproducing grasses.

Technical Abstract: Introductions using vegetative propagules can be essential for safeguarding rare clonal species, especially when seed production is limited or natural populations are highly fragmented. We investigated the genomic consequences of such introductions in Pleuropogon oregonus, a critically endangered rhizomatous grass endemic to wetland habitat in the western United States. Using genome-wide SNP data, we assessed genetic diversity, structure, and relatedness among individuals in extant natural sites separated by approximately 375 km and from two introduction sites where transplants were grown from wild-harvested rhizomes. Our analyses revealed two unique genetic lineages that diverged at least 160,000 years ago with limited subsequent gene flow, which we refer to as the North and South populations. Within these populations, genetic diversity was modest despite extensive clonality. In the North population, eight genetically distinct clones were detected within a single natural site, and the introduction using rhizomes from this natural site retained similar levels of heterozygosity and allelic diversity. In addition, we identified novel genotypes in introduction plots from an older planting effort that used rhizomes from an unsampled natural site. In the South, natural sites were each dominated by one clone or closely related individuals, and the introduction mirrored this low clonal diversity. Across both regions, introductions successfully captured and maintained genotypes from their sources, confirming that vegetative propagation can preserve genetic diversity and increase population redundancy. Genetic characterization prior to the collection of vegetative propagules would enhance representativeness, while post-introduction genomic monitoring can provide critical data for tracking the fitness of individual and population genotypes, which may help inform subsequent introduction efforts. For P. oregonus, this approach has increased the number of extant sites and safeguarded genotypes, offering a replicable model for the recovery of other vegetatively reproducing rare plants.