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Updated: Aug 7, 2026
09:17
Investigation of Plant Interactions Across Common Mycorrhizal Networks Using Rotated Cores
Published on: March 26, 2019
Below-ground interactions with arbuscular mycorrhizal shrubs decrease the performance of pinyon pine and the
Theresa A McHugh1, Catherine A Gehring
1Northern Arizona University, Department of Biological Sciences, Flagstaff, AZ 86001-5640, USA.
The New Phytologist
|June 15, 2006
Summary
Below-ground competition from shrubs negatively impacts pinyon pine growth and ectomycorrhizal (EM) fungi. Removing shrubs improved pinyon growth and doubled EM colonization, highlighting plant-fungi interactions.
Area of Science:
- Ecology
- Plant-soil interactions
- Mycology
Background:
- Below-ground plant interactions are understudied regarding their impact on symbiotic fungi.
- Arbuscular mycorrhizal (AM) shrubs can influence neighboring plants and their associated fungal communities.
Purpose of the Study:
- To investigate how below-ground competition with AM shrubs affects pinyon pine growth.
- To determine the impact of these interactions on the abundance and community composition of ectomycorrhizal (EM) fungi.
Main Methods:
- Combined drought observations with a shrub removal experiment.
- Assessed pinyon pine growth (above- and below-ground) and EM fungal colonization and community composition.
Main Results:
- Shrub density negatively correlated with pinyon growth and explained 75% of EM colonization variation.
- Shrub removal led to increased pinyon fine-root biomass, shoot length, and needle length (competitive release).
- EM fungal colonization doubled after shrub removal, but EM communities showed no significant response due to low diversity.
Conclusions:
- Below-ground competition with AM shrubs negatively affects both pinyon pines and their associated EM fungi.
- These competitive effects may become more prevalent in arid ecosystems facing increased drought frequency and severity.
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