Although microbes influence plant growth, little is known about the impact of microbial diversity on plant fitness trade-offs, intraspecific-interactions, and soil nutrient dynamics in the context of biodiversity-ecosystem functioning (BEF) research. The BEF theory states that higher species richness can enhance ecosystem functioning. Thus, we hypothesize that rhizobacterial species richness will alter sorghum (
To understand factors that influence the assembly of microbial communities, we inoculated
- Award ID(s):
- 1638922
- NSF-PAR ID:
- 10459843
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Environmental Microbiology Reports
- Volume:
- 12
- Issue:
- 1
- ISSN:
- 1758-2229
- Page Range / eLocation ID:
- p. 70-77
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Sorghum bicolor L.) growth, soil nutrient dynamics and interactions (antagonism or synergism) in a nutrient-poor greenhouse soil. Using six rhizobacterial species in a BEF experiment, we tested the impact of a species richness gradient (0, 1, 3, 5 or 6 species per community) on plant growth, nutrient assimilation, and soil nutrient dynamics via seed-inoculation. Our experiment included, one un-inoculated control, six rhizobacterial monoculture(Pseudomonas poae, Pseudomonas sp., Bacillus pumilus., Pantoea agglomerance., Microbacterium sp., andSerratia marcescens ), and their nine mixture treatments in triplicate (48). Rhizobacterial species richness enhanced per pot above- or below-ground dry mass. However, the per plant growth and plant nutrient assimilation declined, most likely, due to microbial-driven competitive interactions among sorghum plants. But nevertheless, some rhizobacterial monoculture and mixture treatments improved per plant (shoot and root) growth and nutrient assimilation as well. Soil nutrient contents were mostly lower at higher plant-associated rhizobacterial diversity; among these, the soil Zn contents decreased significantly across the rhizobacterial diversity gradient. Rhizobacterial diversity promoted synergistic interactions among soil nutrients and improved root–soil interactions. Overall, our results suggest that a higher rhizobacterial diversity may enhance soil–plant interactions and total productivity under resource limited conditions. -
1. Ants are widely regarded as ‘ecosystem engineers’ because their nest construction and contributions to nutrient cycling change the biological, chemical, and physical properties of the soil around their nests. Despite increasing attention to ant manipulation of soil ecosystems, the extent to which many common species influence soil properties, as well as nutrient uptake and community composition of plants near nests, is still unknown.
2. This study tested hypotheses that activities of a common subalpine ant,
, alter soil moisture and pH, redistribute nitrogen around nests, and affect plant species abundance and ground cover.Formica podzolica 3. A combination of field sampling techniques showed that distance from a nest had a positive relationship with soil moisture and a negative relationship with plant abundance next to and downhill from nests. Slope aspect also affected plant communities, with downhill transects having higher plant cover and above‐ground biomass than uphill transects. A stable isotope analysis did not reveal that plants near nests had enriched15N, but there were substantial differences in15N among sites.
4. Overall, this study uncovers significant impacts of
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