Plant-Microbe Interactions (Block 3) Flashcards
What is the phyllosphere?
The environment around the Roots.
What is the rhizosphere?
The Leaf environment.
What are biotrophic pathogens?
Micro-organisms that parasitise LIVING plant cells.
What are necrotrophic pathogens?
Micro-organisms that parasitise DEAD plant cells.
What function as virulence factors for microbial Pathogens?
Effector proteins.
What have plants evolved in response to pathogens’ effector protein virulence factors?
R (resistance) genes.
What do plant R Genes do?
Scan the cellular environment for pathogens’ effector proteins.
What does recognition of (pathogen) effector proteins by an R gene (plant) trigger?
Many plant defence responses, which prevent colonisation.
Once a pathogenic Effector Protein is recognised, what does it become?
An AVIRULENCE (AVR) protein.
What is resistance via R Genes specific to?
Plant Cultivar and Pathogen Race.
How are R Genes used in plant breeding?
R Genes can be identified in wild ecotypes and crossed into commercial cultivars.
Following effector (Avr) / R recognition, which response triggered in the plant is the most conspicuous?
The Hypersensitive Response (HR).
What is The Hypersensitive Response (HR)?
When pathogen EP recognition triggers a cell suicide programme which executes challenged plant cell(s).
Why does the host undergo an HR response upon Pathogen Recognition?
Killing invaded cells removes nutrients from invading
microbial pathogens, preventing infection.
