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Protocols for Investigating the Host-tissue Distribution, Transmission-mode, and Effect on the Host Fitness of a Densovirus in the Cotton Bollworm
Published on: April 12, 2017
Evolution of virulence in a plant host-pathogen metapopulation
Peter H Thrall1, Jeremy J Burdon
1Commonwealth Scientific and Industrial Research Organization (CSIRO)-Plant Industry, Centre for Plant Biodiversity Research, General Post Office Box 1600, Canberra, ACT 2601, Australia. Peter.Thrall@csiro.au
Science (New York, N.Y.)
|March 15, 2003
Summary
In wild flax and rust pathogen populations, pathogen virulence and host resistance varied locally. Selection favors different pathogen strains based on host resistance, consistent with gene-for-gene coevolution models.
Area of Science:
- Ecology
- Evolutionary Biology
- Plant Pathology
Background:
- Wild plant-pathogen interactions are crucial for ecosystem dynamics.
- Local adaptation in host resistance and pathogen virulence is common.
- Gene-for-gene interactions are a key model for understanding coevolution.
Purpose of the Study:
- To investigate the relationship between host resistance and pathogen virulence in a natural system.
- To determine the spatial distribution patterns of pathogen strains.
- To test predictions of gene-for-gene coevolution models.
Main Methods:
- Field surveys of host resistance and pathogen virulence across local populations.
- Experimental inoculations to assess pathogen fitness trade-offs.
- Analysis of spatial distribution and temporal stability of pathogen strains.
Main Results:
- Significant variation in host resistance and pathogen virulence among populations.
- Correlation between high host resistance and frequent broadly virulent pathogens.
- Evidence of a negative trade-off between pathogen spore production and virulence.
- Nonrandom spatial distribution of pathogens suggests strong local selection.
Conclusions:
- Selection favors virulent pathogens in resistant host populations and avirulent strains in susceptible populations.
- Trade-offs are essential for maintaining genetic variation and preventing pathogen virulence from exceeding host resistance.
- Findings support gene-for-gene models of host-pathogen coevolution in natural systems.
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