Soil properties and plant functional traits have different importance in shaping rhizosphere soil bacterial and fungal communities in a meadow steppe

Soil properties and plant functional traits are important factors
influencing rhizosphere microbial diversity and composition. However,
their divergent roles in shaping rhizosphere bacterial and fungal
communities remain poorly understood. Additionally, the influence of plant
resource acquisition strategies on these microbial communities is not well
documented. We collected 147 rhizosphere soil, leaf, and root samples from
around 18 plant species in a meadow steppe in northern China. We
determined the bacterial and fungal communities in the rhizosphere soil
through high-throughput sequencing. Our analysis revealed that soil
properties and plant traits differed in their importance for influencing
the diversity and composition of rhizosphere bacteria and fungi.
Specifically, soil properties had a more pronounced regulatory effect on
bacterial diversity than on fungal diversity. Furthermore, soil properties
exerted a stronger influence on the composition of rhizosphere fungal
communities compared to plant traits; while both factors similarly
affected bacteria community composition. This discrepancy might be
attributed to differences in dispersal limitations between bacteria and
fungi. We also found that plant resource acquisition strategies
significantly impacted both diversity and composition of rhizosphere
microbial communities, with plants employing ‘fast-growing’ strategies
exhibiting lower fungal diversity. Moreover, conservation-related traits
of plants had a more pronounced effect on fungal community composition
than root collaboration-related traits. These novel findings demonstrate
that soil properties and plant traits play distinct roles in shaping
rhizosphere soil bacterial and fungal communities. The linkages between
plant resource acquisition strategy and rhizosphere microbial communities
could enhance our understanding of the complex interactions between plants
and their associated microorganisms.