Data from: Field heritability of a plant adaptation to fire in heterogeneous landscapes

The strong association observed between fire regimes and variation in
plant adaptations to fire suggests a rapid response to fire as an agent of
selection. It also suggests that fire-related traits are heritable, a
precondition for evolutionary change. One example is serotiny, the
accumulation of seeds in unopened fruits or cones until the next fire, an
important strategy for plant population persistence in fire-prone
ecosystems. Here, we evaluate the potential of this trait to respond to
natural selection in its natural setting. For this, we use a SNP marker
approach to estimate genetic variance and heritability of serotiny
directly in the field for two Mediterranean pine species. Study
populations were large and heterogeneous in climatic conditions and fire
regime. We first estimated the realized relatedness among trees from
genotypes, and then partitioned the phenotypic variance in serotiny using
Bayesian animal models that incorporated environmental predictors. As
expected, field heritability was smaller (around 0.10 for both species)
than previous estimates under common garden conditions (0.20). An estimate
on a subset of stands with more homogeneous environmental conditions was
not different from that in the complete set of stands, suggesting that our
models correctly captured the environmental variation at the spatial scale
of the study. Our results highlight the importance of measuring
quantitative genetic parameters in natural populations, where
environmental heterogeneity is a critical aspect. The heritability of
serotiny, although not high, combined with high phenotypic variance within
populations, confirms the potential of this fire-related trait for
evolutionary change in the wild.