Analysis of the spatial genetic structure of Passiflora incarnata in recently disturbed sites
Rebecca T. Tague and Stephanie A. Fore
Abstract: In early successional species, short life span
and frequent spatial relocation may affect the distribution of genetic
variation but the pattern may be altered by reproductive patterns. Passiflora
incamata L. (Passifloraceae), an early successional vine found throughout
the southeastern United States, reproduces sexually and asexually through
clonal sprouts. We examined the genetic structure of P. incamata in
recently disturbed habitats at three spatial scales: within a patch, among
patches separated by 250 m, and between sites separated by 10 km. Genetic
variation may be clumped at the scale of neighboring plants if stem resprouting
is significant. In each patch, eleven arbitrarily selected plants and
their four nearest neighbors were mapped and leaf samples were collected
for genetic analysis. The
multilocus genotype of each individual for seven polymorphic allozymes
was determined. Potential clones were determined by estimating the probability
of a second occurrence of each genotype and a multilocus coefficient of
coancestry (Pi). Data indicated P. incamata was reproducing primarily
sexually. Most of the genetic variation was within a patch with little
variation among patches. These data suggest that the genetic structure
of this colonizing species was determined by founder effects interacting
with long distance pollen movement.
Key words: allozymes, passionflower, spatial, genetic structure,
early colonizer, Passiflora incamata.
SREL Reprint #2861
Tague, R. T. and S. A. Foré. 2005. Analysis of the spatial genetic structure of Passiflora incarnata in recently disturbed sites. Canadian Journal of Botany 83:420-426.
