Native Microbes Amplify Native Seedling Establishment and Diversity While Inhibiting a Non-Native Grass

Area of Science:

• Ecology
• Restoration Ecology
• Microbial Ecology

Background:

• Native plant establishment is crucial for grassland restoration.
• The role of soil microbes in mediating plant community dynamics, especially against invasive species, requires further investigation.
• Non-native grasses like Setaria faberi pose significant challenges to native grassland recovery.

Purpose of the Study:

• To investigate the impact of native soil microbial communities on native seedling recruitment and establishment.
• To assess how microbial amendments influence plant diversity and biomass in the presence of a non-native competitor.
• To determine the efficacy of specific microbial inoculants (ex-arable soil, late successional arbuscular mycorrhizal fungi) in enhancing native plant success.

Main Methods:

• Experimental setup involved seeding pots with native prairie seeds and the invasive grass Setaria faberi.
• Soil treatments included: ex-arable whole soil, late successional arbuscular mycorrhizal (AM) fungi, a combination of both, and sterile soil (control).
• Evaluated seedling biomass, native plant abundance, late successional plant abundance, total plant diversity, and abundance of the non-native grass S. faberi.

Main Results:

• The treatment combining native AM fungi and ex-arable whole soil resulted in the greatest native plant abundance, late successional plant abundance, and overall diversity.
• This enhanced native plant growth and diversity led to a significant decrease in the abundance of the invasive grass S. faberi.
• Native AM fungi positively influenced late successional plant establishment, contrary to expectations for early successional plants.

Conclusions:

• Late successional native microbes are vital for successful native seed establishment in restoration settings.
• Microbial amendments can be effectively utilized to increase plant community diversity and invasibility resistance in early restoration stages.
• Harnessing specific native microbial communities offers a promising strategy for managing invasive species and promoting resilient grassland ecosystems.