Phylogenetic dependence of plant-soil feedback promotes rare species in
a subtropical forest
Abstract
The widespread observation that rare species have stronger conspecific
plant-soil feedback (PSF) than common species raises more questions than
answers on how rare species can possibly win the dance with abundant
species. Here, we test soil feedback effect of phylogenetically related
species on seedlings of contrasting local abundance in a subtropical
forest. The results showed that although rare species suffered strong
negative PSF in soils of conspecifics or phylogenetically close
relatives, no such feedback was found in the soils of distant relatives.
In contrast, although common species had weak conspecific PSF, they
suffered consistently strong heterospecific soil feedback. These
mechanisms ensure that rare species would fare well in the neighborhood
of phylogenetically distant heterospecifics but do poorly under their
close relatives, while common species perform relatively well in their
own neighborhood but poorly in others’. This phylogenetic conservatism
in PSF facilitates the persistence of rare species in a community.