Fine-scale spatial genetic structure, mating and gene flow dispersal patterns in Parkia biglobosa populations under different levels of habitat fragmentation

PREMISE: A good understanding of genetic variation and gene dispersal in tree populations is crucial for their sustainable management, particularly in a context of rapid environmental changes. West African Sudanian savannahs are undergoing fragmentation and degradation, partly due to expansion of crop cultivation and monocultures that reduce tree density and may impact pollinators. This could affect the population dynamics of important indigenous trees. We investigated the influence of habitat fragmentation on patterns of genetic diversity and gene dispersal of a key Sudanian agroforestry tree species, Parkia biglobosa.

METHODS: Using ten highly polymorphic nuclear microsatellites, we genotyped 2475 samples from reproductive trees, seedlings and embryos in four tree populations presenting different levels of habitat fragmentation.

RESULTS: Parkia biglobosa presented high genetic diversity, similar across the four populations studied. Genetic diversity and inbreeding were similar b...