| Abstract Detail
Population Genetics/Genomics Trapnell, Dorset [1], Smallwood, Patrick [2], Dixon, Kingsley [3], Phillips, Ryan [4]. Are small populations larger than they seem? Genetic insights into small, patchily distributed Drakaea glyptodon (Orchidaceae) populations. Many species of orchids are characterized by small, patchily distributed populations. Resolving how orchids persist in such populations is important for understanding the ecology and long-term persistence of this hyper-diverse family, many members of which are of conservation concern. Our focal species is the common terrestrial orchid Drakaea glyptodon from Southwest Australia, which relies on sexually deceived male thynnine wasps for pollination. Ten populations of D. glyptodon were genotyped with ten nuclear and five chloroplast SSR markers. Levels and partitioning of genetic variation, and effective population sizes (Ne) were estimated. The relative contributions of pollen and seed-mediated gene movement to overall gene flow was evaluated using the mp / ms ratio. Spatial genetic structure was estimated using nuclear data, and together with plastid data, used to infer the effective number of seed parents per population. We found high levels of nuclear and chloroplast diversity, estimated Ne values that generally exceed predictions based on the number of flowering individuals, and moderate levels of gene flow. A value of 3.65 for mp /ms indicates that pollinators play a greater role than seed in introducing genetic diversity to populations via gene flow. Two populations were founded by fewer than five colonists, suggesting that populations are colonized by few seeds, with population growth largely resulting from in situ recruitment. Our results highlight that D. glyptodon is highly effective at persisting in patchily distributed populations. However, it is important to examine how insights from this common, widespread species transfer to species that are rare and/or occur in fragmented landscapes. Log in to add this item to your schedule
1 - Boise State University, Snake River Plains Herbaria, , Boise, Idaho, 83725, USA 2 - University of Georgia, Department of Plant Biology, 2502 Miller Plant Sciences, 120 Carlton St., Athens, GA, 30605, United States 3 - Curtin University, Department of Environment and Agriculture, Kent Street, Bentley, 6102 WA, Australia 4 - La Trobe University, Department of Ecology, Environment and Evolution, Melbourne, Victoria 3086, Australia
Keywords: Chloroplast haplotypes Population Genetics Seed dispersal Genetic diversity gene flow SSRs Effective population size.
Presentation Type: Oral Paper Session: PGG1, Population Genetics and Genomics I Location: / Date: Tuesday, July 20th, 2021 Time: 3:30 PM(EDT) Number: PGG1003 Abstract ID:418 Candidate for Awards:Margaret Menzel Award |