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A Rapid and Efficient Method for Assessing Pathogenicity of Ustilago maydis on Maize and Teosinte Lines
Published on: January 3, 2014
Southern corn leaf blight: susceptible and resistant mitochondria
Science (New York, N.Y.)
|July 2, 1971
Summary
Helminthosporium maydis pathotoxin disrupts respiration and causes swelling in susceptible corn mitochondria, but not in resistant corn. This reveals a key mechanism of corn blight susceptibility.
Area of Science:
- Plant Pathology
- Mitochondrial Physiology
- Biochemistry
Background:
- Corn blight, caused by Helminthosporium maydis (race T), devastates crops.
- Understanding the molecular basis of plant-pathogen interaction is crucial for disease resistance.
Purpose of the Study:
- To investigate the effects of Helminthosporium maydis pathotoxin on corn mitochondria.
- To differentiate responses between susceptible and resistant corn genotypes.
Main Methods:
- Isolation of mitochondria from etiolated shoots of susceptible and resistant corn.
- Exposure of isolated mitochondria to Helminthosporium maydis pathotoxin in various respiratory states.
- Measurement of respiratory rate, oxidative phosphorylation, and mitochondrial swelling.
Main Results:
- Pathotoxin induced changes in respiratory rate and oxidative phosphorylation in susceptible corn mitochondria.
- Susceptible corn mitochondria exhibited immediate, irreversible swelling upon pathotoxin addition.
- Mitochondria from resistant corn showed no response to the pathotoxin.
Conclusions:
- The pathotoxin directly affects mitochondrial function and membrane integrity in susceptible corn.
- Mitochondrial swelling is linked to the observed respiratory and coupling effects.
- Genetic resistance in corn involves an inability of mitochondria to respond to the pathotoxin.
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