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09:17
Investigation of Plant Interactions Across Common Mycorrhizal Networks Using Rotated Cores
Published on: March 26, 2019
Within-population genetic variability in mycorrhizal interactions
Jason D Hoeksema1, Bridget J Piculell, John N Thompson
1Department of Ecology and Evolutionary Biology; University of California, Santa Cruz; Santa Cruz, CA USA.
Communicative & Integrative Biology
|August 26, 2009
Summary
Coevolutionary selection varies across environments. This study found fungal genotypes differed in compatibility with pine hosts, suggesting ongoing selection on the fungus, Rhizopogon occidentalis.
Area of Science:
- Ecology
- Evolutionary Biology
- Plant-Fungal Interactions
Background:
- The geographic mosaic theory of coevolution posits that natural selection on species interactions differs across ecosystems.
- This variation can lead to diverse ecological outcomes, from mutualism to parasitism.
- Previous work showed genetic variation in symbiotic compatibility between bishop pine (Pinus muricata) and the ectomycorrhizal fungus Rhizopogon occidentalis.
Purpose of the Study:
- To investigate genetic variation for symbiotic compatibility in the interaction between shore pine (Pinus contorta var. contorta) and Rhizopogon occidentalis.
- To determine if fungal lineages adapt to individual trees.
- To test the geographic mosaic theory in a new plant-fungus system.
Main Methods:
- A laboratory experiment using shore pine (Pinus contorta var. contorta) and two genotypes of the ectomycorrhizal fungus Rhizopogon occidentalis.
- Assessing symbiotic compatibility and fungal colonization intensity.
- Measuring the effect of fungal symbionts on plant growth.
Main Results:
- No genetic variation in compatibility was found among shore pine lineages.
- No evidence of fungal adaptation to individual shore pine trees.
- Significant differences in compatibility existed between the two fungal genotypes, with one genotype showing reduced colonization and negative effects on plant growth.
Conclusions:
- Results suggest ongoing natural selection on Rhizopogon occidentalis for varying symbiotic compatibility with different pine hosts.
- Mechanisms generating and maintaining this genetic variation remain undetermined.
- Findings contribute to understanding plant-symbiont coevolution across geographic ranges.
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