Data from: Evidence of high genetic diversity and significant population structuring in Vachellia tortilis (Forsk.) Galasso & Bonfi population in Kenya
Omondi, Stephen F. et al. (2019), Data from: Evidence of high genetic diversity and significant population structuring in Vachellia tortilis (Forsk.) Galasso & Bonfi population in Kenya, Dryad, Dataset, https://doi.org/10.5061/dryad.6s82f20
Context: Vachellia tortilis is an important dryland tree species valued for fuelwood and fodder production, however, no strategy has been put in place for sustainable management of the species genetic resources. Furthermore, there is inadequate information on the species population genetics to facilitate development of such strategies. Aim: We evaluated the amount and structure of neutral genetic diversity of V. tortilis population in Kenya and provided recommendations necessary for improvement and conservation of the species genetic resources. We hypothesised that the current genetic diversity of V. tortilis is high because of it is demographic history and that no population structuring was expected to occur due to the presumed long distance and effective gene flow within the species. Methods: Leaf tissues were collected from fifteen putative natural populations of V. tortilis covering the whole distribution range in Kenya. DNA was isolated from the leaf tissues and analysed using microsatellite markers. In total, 450 trees were genotyped using 10 polymorphic nuclear microsatellite loci, and genetic diversity and population structure parameters determined Results: We found high levels of genetic diversity within the populations with a mean gene diversity at 0.85. However, significant population differentiation was evident (FST = 0.026, P = 0.007; RST = 0.032, P = 0.004) despite large number of migrants per generation (Nm = 5.3). Population structure detected suggests presence of two clusters, although, some populations showed mixed ancestry. The groups reflect the influence of geographic patterns and historical population gene flow. Conclusion: There exist high genetic diversity in V. tortilis in Kenya with significant population structuring into two clusters. We recommend consideration of the two distinct groups in the development of the species improvement, breeding and conservation programmes. Such programmes should ensure maintenance of the majority of the extant genetic diversity.