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The Neotropical tree Parkia panurensis shows a spatial genetic structure from the seed to the adult stage that is most likely the outcome of the seed dispersal provided by primates. Seed dispersal and pollination determine the gene flow within plant populations. In addition, seed dispersal creates the template for subsequent stages of plant recruitment. Therefore, the question arises whether and how seed dispersal affects the spatial genetic structure (SGS) of plant populations. In this study, we used microsatellites to analyse the SGS of the Neotropical tree Parkia panurensis (Fabaceae). This plant species is a major food resource for primates and its seeds are mainly dispersed by primates. Seeds were collected during behavioural observations of a tamarin mixed-species troop in north-eastern Peru. Additionally, leaf samples of juveniles and of adults trees of this species were collected throughout the home range of the tamarin troop. A significant SGS for embryos (located within the dispersed seeds) and for non-reproductive plants are found up to a distance of 300 m. This matches the distance within which most seeds are dispersed. In the adult stage, the scale of a significant SGS is reduced to 100 m. While we cannot explain this scale reduction, our study provides the first evidence that primate seed dispersal does influence the SGS of a tropical tree species.

In contrast to many plant species, which had not survived in Central Europe during the last glacial maximum (LGM) and therefore recolonized from various southern or eastern refugia, we put forward the hypothesis that Juniperus communis L., a species with large ecological amplitude, could have survived in a cold steppe-like biome of the LGM throughout Central Europe. Fossils from locations above the 50th latitude dating back to 15 000—11 000 BP lead to this assumption. However, there is an absolute lack of records for the LGM. We used DNA markers to obtain genetic support for our hypothesis. If common juniper had survived in Central Europe and had not recolonized this area from diverse outside refugia, we would expect the gene pool of J. communis being imprinted in a different way than what is common for classic Holocene ‘recolonizers’. The latter tend to exhibit profound large-scale isolation-by-distance effects where genetic distances are positively correlated with geographic distances. Using AFLP (Amplified Fragment Length Polymorphism) markers in 23 modern common juniper populations sampled throughout Europe, we found a high level of genetic differentiation. However, there are no underlying phylogeographic signals or any other meaningful geographic genetic structures. Consistent with a scenario of perglacial survival there is no correlation between genetic and geographic distances as a result from Mantel tests.The present study again demonstrates the power of genetic tools when fossil records are not available. It contributes to an increasing knowledge about species distribution during unfavourable climatic conditions.

• Premise of the study: We present here a set of nine polymorphic nuclear microsatellite loci, identified for the first time within the neotropical legume tree species Parkia panurensis Benth. ex H. C. Hopkins, which is widespread in western and central Amazonia. • Methods and Results: To characterize these loci, 33 Parkia panurensis adult trees were analyzed. The number of alleles ranged from eight to 32, with an average of 14.4 alleles per locus. Mean expected heterozygosity ranged from 0.74 to 0.955. • Conclusions: All nine loci could also be verified in six other Parkia species and polymorphic fragments amplified. The new marker set can be used for future studies of genetic diversity and differentiation, as well as estimation of gene flow and parentage analyses in various Parkia species. peerReviewed

Eleven polymorphic nuclear microsatellite markers for Abies alba Mill. were developed from an enriched genomic library. An average of 5.2 alleles per locus and a mean expected heterozygosity of 0.532 were found in a sample of 24 Abies alba individuals from different populations within Europe. These loci can be used in studies of genetic diversity for parentage analysis and for estimation of gene flow in silver fir populations. Moreover, successful amplifications were obtained for eight other Mediterranean Abies species, suggesting that these loci may be useful for similar applications in other fir species.

Background: Determining the distances over which seeds are dispersed is a crucial component for examining spatial patterns of seed dispersal and their consequences for plant reproductive success and population structure. However, following the fate of individual seeds after removal from the source tree till deposition at a distant place is generally extremely difficult. Here we provide a comparison of observationally and genetically determined seed dispersal distances and dispersal curves in a Neotropical animal-plant system. Methodology/Principal Findings: In a field study on the dispersal of seeds of three Parkia (Fabaceae) species by two Neotropical primate species, Saguinus fuscicollis and Saguinus mystax, in Peruvian Amazonia, we observationally determined dispersal distances. These dispersal distances were then validated through DNA fingerprinting, by matching DNA from the maternally derived seed coat to DNA from potential source trees. We found that dispersal distances are strongly rightskewed, and that distributions obtained through observational and genetic methods and fitted distributions do not differ significantly from each other. Conclusions/Significance: Our study showed that seed dispersal distances can be reliably estimated through observational methods when a strict criterion for inclusion of seeds is observed. Furthermore, dispersal distances produced by the two primate species indicated that these primates fulfil one of the criteria for efficient seed dispersers. Finally, our study demonstrated that DNA extraction methods so far employed for temperate plant species can be successfully used for hardseeded tropical plants. peerReviewed

 Premise of the study: We present a set of 12 polymorphic nuclear microsatellite loci, identifi ed for the fi rst time within the herbaceous plant species Cnidium dubium (Schkuhr) Thell. using next-generation sequencing.  Methods and Results: To characterize these loci, 40 plants were analyzed genetically. The number of alleles ranged from 2 to 23, with an average of 8.3 alleles per locus. Mean observed and expected heterozygosities ranged from 0.25 to 0.95 and 0.30 to 0.94, respectively.  Conclusions: All 12 nuclear microsatellite loci showed scorable and polymorphic fragments after polymerase chain reaction. The new marker set can be used for future studies of genetic diversity and differentiation as well as estimation of gene fl ow and spatial genetic structures.

We developed five nuclear microsatellite markers in Juniperus communis L. using an enriched library method. Samples from 28 juniper individuals were collected in Spain, Germany and Slovakia and were analysed at the five loci. A high level of allelic diversity with values ranging from nine to 23 alleles was found. These highly polymorphic markers will be used in ongoing population genetic studies to evaluate the genetic resources and to contribute to the maintenance of genetic diversity of juniper in Middle Europe.

Background Population extinction risk in a fragmented landscape is related to the differential ability of the species to spread its genes across the landscape. The impact of landscape fragmentation on plant population dynamics will therefore vary across different spatial scales. We quantified successful seed-mediated dispersal of the dioecious shrub Juniperus communis in a fragmented landscape across northwestern Europe by using amplified fragment length polymorphism (AFLP) markers. Furthermore we investigated the genetic diversity and structure on two spatial scales: across northwestern Europe and across Flanders (northern Belgium). We also studied whether seed viability and populations size were correlated with genetic diversity. Results Unexpectedly, estimated seed-mediated dispersal rates were quite high and ranged between 3% and 14%. No population differentiation and no spatial genetic structure were detected on the local, Flemish scale. A significant low to moderate genetic differentiation between populations was detected at the regional, northwest European scale (PhiPT = 0.10). In general, geographically nearby populations were also genetically related. High levels of within-population genetic diversity were detected but no correlation was found between any genetic diversity parameter and population size or seed viability. Conclusions In northwestern Europe, landscape fragmentation has lead to a weak isolation-by-distance pattern but not to genetic impoverishment of common juniper. Substantial rates of successful migration by seed-mediated gene flow indicate a high dispersal ability which could enable Juniperus communis to naturally colonize suitable habitats. However, it is not clear whether the observed levels of migration will suffice to counterbalance the effects of genetic drift in small populations on the long run.