Nematodes surfing the waves: long-distance dispersal of soil-borne microfauna via sea swept rhizomes


E. de la Peña, Dept of Biology, Faculty of Sciences, Ghent Univ., K.L. Ledeganckstraat 35, BE-9000 Ghent, Belgium. E-mail:


Dispersal mechanisms of soil-borne microfauna have hitherto received little attention. Understanding dispersal mechanisms of these species is important to unravel their basic life history traits, biogeography, exchange of individuals between populations, and local adaptation. Soil-borne nematodes and root-feeding nematodes in particular occupy a key position in soil-food webs and can be determinants for plant growth and vegetation structure and succession. However, their dispersal abilities have been scarcely addressed, predominantly focusing on species of agricultural importance. Still, root-feeding nematodes are usually considered as being extremely limited and bound to the rhizosphere of plants. We investigated a mechanism for long distance dispersal of root-feeding nematodes associated to two widespread coastal dune grasses. The nematodes are known to be crucial for the functioning of these grasses. We experimentally tested the hypothesis that root-feeding nematodes are able to move across long distances inside rhizome fragments that are dispersed by seawater. We also tested the survival capacities of the host plants in seawater. Our study demonstrates that root-feeding nematodes and plants are able to survive immersion in seawater, providing a mechanism for long distance dispersal of root feeding nematodes together with their host plant. Drifting rhizome fragments enable the exchange of plant material and animals between dune systems. These results provide new insights to understand the ecology of dune vegetation, the interaction with soil-borne organisms and more importantly, re-set the scale of spatial dynamics of a group of organisms considered extremely constrained in its dispersal capacities.