Contemporary pollen and seed dispersal in a Prunus mahaleb population: patterns in distance and direction

Abstract

Pollination and seed dispersal determine the spatial pattern of gene flow in plant populations and, for those species relying on pollinators and frugivores as dispersal vectors, animal activity plays a key role in determining this spatial pattern. For these plant species, reported dispersal patterns are dominated by short-distance movements with a significant amount of immigration. However, the contribution of seed and pollen to the overall contemporary gene immigration is still poorly documented for most plant populations. In this study we investigated pollination and seed dispersal at two spatial scales in a local population of Prunus mahaleb (L.), a species pollinated by insects and dispersed by frugivorous vertebrates. First, we dissected the relative contribution of pollen and seed dispersal to gene immigration from other parts of the metapopulation. We found high levels of gene immigration (18.50%), due to frequent long distance seed dispersal events. Second, we assessed the distance and directionality for pollen and seed dispersal events within the local population. Pollen and seed movement patterns were non-random, with skewed distance distributions: pollen tended moved up to 548 m along an axis approaching the N-S direction, and seeds were dispersed up to 990 m, frequently along the SW and SE axes. Animal-mediated dispersal contributed significantly towards gene immigration into the local population and had a markedly nonrandom pattern within the local population. Our data suggest that animals can impose distinct spatial signatures in contemporary gene flow, with the potential to induce significant genetic structure at a local level.

Contemporary pollen flow, characterization of the maternal ecological neighbourhood and mating patterns in wild cherry (Prunus avium L.)

“…The Garcia et al (2007) site is located at an altitude of 1615 m above sea level (asl) whereas our study site is at B150 m asl. Insect flight distances may be longer in the lower altitude site where conditions are likely to be less windy.…”

Probability of successful larval dispersal declines fivefold over 1 km in a coral reef fish

“…However, direct measures of the relationship between the probability of successful dispersal and distance between populations are lacking. Direct measures, obtained by tracing individual larvae back to their parents using molecular markers, will generate new insights and enable us to test predictions of biophysical models, just as they have been carried out in terrestrial systems [33][34][35][36][37].…”

Wind-borne insects mediate directional pollen transfer between desert fig trees 160 kilometers apart

“…However, many plant species depend on insects to transport their pollen, and so the behavior of their particular pollinators determines how far pollen is transported. Pollen flow is commonly skewed toward short distances of just a few meters, reflecting insect behavior and the spacing of the plants (2,3), but some obligate out-breeding plant species form widely scattered populations, with individuals growing far apart. Long-distance dispersal can be mediated by wind, water, or animal vectors and is normally associated with specific but rare events (4) rather than through frequent long-distance movements.…”