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A Method to Preserve Wetland Roots and Rhizospheres for Elemental Imaging
Published on: February 15, 2021
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To Fix or Not To Fix: Controls on Free-Living Nitrogen Fixation in the Rhizosphere
Darian N Smercina1, Sarah E Evans2, Maren L Friesen3
1Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing, Michigan, USA marinisd@msu.edu.
Applied and Environmental Microbiology
|January 20, 2019
Summary
Free-living nitrogen fixation (FLNF) is crucial for plant nitrogen supply. Understanding controls on FLNF in the rhizosphere is vital for sustainable agriculture and reducing fertilizer use.
Area of Science:
- Agricultural Science
- Microbiology
- Environmental Science
Background:
- Free-living nitrogen fixation (FLNF) by rhizosphere bacteria is a significant nitrogen source in terrestrial ecosystems.
- FLNF offers a sustainable alternative to chemical fertilizers, reducing costs and environmental impact.
- A mechanistic understanding of FLNF controls is lacking, hindering its application in agriculture.
Purpose of the Study:
- To provide a mechanistic overview of FLNF controls in the rhizosphere.
- To compare FLNF with symbiotic nitrogen fixation.
- To contextualize FLNF in managed systems using the bioenergy crop switchgrass (Panicum virgatum).
Main Methods:
- Mechanistic overview of FLNF.
- Comparison of FLNF with symbiotic nitrogen fixation.
- Case study application to switchgrass (Panicum virgatum).
Main Results:
- FLNF occurs under diverse rhizosphere conditions, distinct from symbiotic fixation.
- Carbon, oxygen, nitrogen, and nutrient availability are key controls on FLNF.
- FLNF's role in switchgrass systems requires further investigation.
Conclusions:
- Understanding FLNF controls is essential for harnessing its potential in agriculture.
- Further research is needed to assess FLNF's environmental function and contribution to plant productivity.
- FLNF presents a promising avenue for sustainable nitrogen management in cropping systems.
Keywords:
diazotrophsenvironmental controlsfree-living nitrogen fixationrhizosphererhizosphere-inhabiting microbesMore Related Videos
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