Community-level interactions between plants and soil biota during range expansion

1. Plant species that expand their range in response to current climate
change will encounter soil communities that may hinder, allow, or even
facilitate plant performance. It has been shown repeatedly for plant
species originating from other continents that these plants are less
hampered by soil communities from the new than from the original range.
However, information about the interactions between intra-continental
range expanders and soil communities is sparse, especially at community
level. 2. Here we used a plant-soil feedback experiment approach to
examine if the interactions between range expanders and soil communities
change during range expansion. We grew communities of range-expanding and
native plant species with soil communities originating from the original
and new range of range expanders. We determined the composition of fungi,
bacteria and nematodes in these conditioned soils by high-throughput
amplicon sequencing of the ITS region and the 16S rRNA gene and using
morphological methods, respectively. Then we tested how these soil
communities influence the growth of subsequent communities of range
expanders and natives. 3. We found that after the conditioning phase soil
bacterial, fungal and nematode communities differed by origin and by
conditioning plant communities. Despite differences in bacterial, fungal
and nematode communities between original and new range, soil origin did
not influence the biomass production of plant communities. Both native and
range expanding plant communities produced most aboveground biomass in
soils that were conditioned by plant communities distantly related to
them. 4. Synthesis. We conclude that communities of range-expanding plant
species shape specific soil communities in both original and new range
soil. Plant-soil interactions of range expanders in communities can be
similar to the ones of their closely related native plant species.