Data from: Does long distance pollen dispersal preclude inbreeding in tropical trees? Fragmentation genetics of Dysoxylum malabaricum in an agro-forest landscape

Tropical trees often display long distance pollen dispersal, even in
highly fragmented landscapes. Understanding how patterns of spatial
isolation influence gene flow and interact with background patterns of
fine scale spatial genetic structure are critical for evaluating the
genetic consequences of habitat fragmentation. In the endangered tropical
timber tree Dysoxylum malabaricum (Meliaceae) we apply eleven
microsatellite markers with paternity and parentage analysis to directly
estimate contemporary gene flow across a large area (216 km2) in a highly
fragmented agro-forest landscape. A comparison of genetic diversity and
genetic structure in adult and juvenile life stages indicates an increase
of differentiation and fine-scale spatial genetic structure (FSGS) over
time. Paternity analysis and parentage analysis demonstrate high genetic
connectivity across the landscape by pollen dispersal. A comparison
between mother trees in forest patches with low and high densities of
adult trees shows that the frequency of short distance mating increases,
as does average kinship among mates in low density stands. We interpret
this as an early warning sign of potentially negative genetic consequences
of forest fragmentation. Single isolated trees, in contrast, frequently
receive heterogeneous pollen from distances exceeding five kilometres. We
discuss the processes leading to the observed patterns of gene flow and
the implications of this for conservation management of D. malabaricum and
tropical trees more generally.