Bjerregaard, Lee S. , Wolf, Paul G. .
Highly structured populations of a narrow endemic primrose.
Maguire Primrose (Primula maguirei L.O. Williams) is a narrow endemic currently listed as threatened (U.S. Fish and Wildlife Service 1985). P. maguirei displays the heterostyly reproductive strategy characteristic of many Primulas. It grows in shallow soils and dolomitic cliffs along a 19 km stretch of Logan canyon, in northern Utah. Its range consists of two distinct groups approximately 12 km apart. Maguire Primrose is probably an obligate outcrosser and a presumed insect pollinator. Yet, the species is distributed among nearby populations that are genetically quite distinct. Evidence for such a genetic structure comes from a previous study using allozyme electrophoresis which indicated that for some loci alternate alleles were fixed or nearly fixed between the two population groups. We now used amplified fragment polymorphisms (AFLPs) to examine many more loci than the previous study and further test the hypothesis of a high degree of genetic structuring in populations of P. maguirei. Data from more than 100 AFLP loci also reveal the distinct pattern of two population groups. Results from a complimentary breeding experiment will also be presented. Individual plants in each population were bagged and hand-pollinated using pollen from other populations. Seed set data were used to infer the presence of possible reproductive barriers between the two population groups. In addition to the AFLP and seed set data, chloroplast DNA sequences were compared among populations of P. magurei. Possible explanations for the highly structured population of P. magurei will be discussed. These include glacial refugia and selection occurring in different microhabitats.
1 - Utah State University, Department of Biology, College of Science, 5305 Old Main Hill, Logan, Utah, 84322-0305, United States
Presentation Type: Paper
Location: Peruvian (Cliff Lodge)
Date: Wednesday, August 4th, 2004
Time: 11:00 AM