Data from: Genetic structure of a naturally regenerating post-fire seedling population: Pinus halepensis as a case study

To study the effects of wildfire on population genetics of a wind
pollinated and wind dispersed tree, we have analyzed the genetic structure
of a post-fire, naturally regenerating seedling population of Pinus
halepensis Miller, on Mt. Carmel, Israel. We tested the existence of
spatial genetic structure, which is expected due to the special spatial
demographic structure of the post-fire seedling and sapling populations of
this species. Explicitly, we asked whether or not seedlings that
germinated under large, burned, dead pine trees are also their offspring.
The results revealed that the post-fire seedling population is
polymorphic, diverse, and reflects the pre-fire random mating system. In
contrast to our prediction, we found no division of the post-fire seedling
population to distinct sub-populations. Furthermore, as a result of
post-fire seed dispersal to longer range than the average pre-fire
inter-tree distance, seedlings found under individual burned trees were
not necessarily their sole offspring. Although the population as a whole
showed a Hardy-Weinberg equilibrium, significant excess of heterozygotes
was found within each tallest seedlings group growing under single, large,
burned pine trees. Our finding indicates the possible existence of intense
natural selection for the most vigorous heterozygous genotypes that are
best adapted to the special post-fire regeneration niche, which is the
thick ash bed under large, dead, pine trees.