Hardcastle, Edith .
Conservation genetics of Moore’s Delphinium (Delphinium newtonianum), an Interior Highlands endemi.
Delphinium newtonianum (Ranunculaceae) is a rare endemic of the Interior Highlands region. The genetic diversity and genetic structure was determined for this species and ecological variables that directly influence the genetics were assessed.Five populations (10 individuals from each population) from the northern region of the highlands Ozark Mountains) and four populations from the southern region of the highlands (Ouachita Mountains) were chosen to study these variables. Sequences from the fourth intron of PepC (phosphoenolpyruvate carboxylase), a single copy, nuclear gene, was used to assess these variables.Genetic diversity in D. newtonianum is high (37 haplotypes were identified from 80 individuals).However, these results are consistent with other rare Delphinium species. Analysis of genetic structure indicates that populations within the Ozark region do not show significant genetic differentiation due to high level of gene flow between populations. However, Ouachita populations have undergone genetic drift and the loss of genetic diversity relative to Ozark populations.In addition, all Ouachita populations are significantly differentiated from all other populations.A neighbor-joining tree based on genetic distance shows that Ouachita populations are more closely related to each other than any Ozark population. Delphinium newtonianum from the Ouachitas have had the time and space (100 km) necessary to develop significant differences from Ozark populations and have advanced along a separate evolutionary trajectory. Delphinium newtonianum consists of two separate evolutionary significant units (ESUs). If possible, genetic material from each region should not be mixed in order to conserve natural patterns of variation. In addition, management agencies should strive to conserve populations in both regions in order to conserve the full range of genetic diversity in the species.
1 - University of Southern Indiana, Biology, 8600 University Boulevard, Evansville, Indiana, 47712, USA
Presentation Type: Paper
Location: Peruvian (Cliff Lodge)
Date: Wednesday, August 4th, 2004
Time: 10:30 AM