Natural Resistance to Plant Pathogens Flashcards
(17 cards)
What are the two preformed defences?
Waxy cuticle & Trichomes
How do waxy cuticles prevent fungal infection?
Physical barrier
chemical inhibitions
Removes moisture required for spore germination
How do Trichomes act as preformed defence against?
The hairs provide both physical and chemical barriers.
What are plants form of chemical defences?
Antimicrobial metabolites.
What do plants lack in immunity?
Mobile defender cells and adaptive immune systems.
What are a plants mode of immunity?
Innate immunity;
Physical barriers
chemical barriers
Cellular defences
How do plants perceive pathogen attack?
Receptors bind and recognise non-self molecules.
What pathogenic structures trigger plant defense response?
Chitins; cell walls of fungi
Glucans; cell walls of fungi & oomycetes
Lipopolysaccharides; Bacterial membrane
Flagella
What are PAMPs?
Pathogen Associated Molecular Patterns
What entry sites to pathogens use in plants?
Through stoma, wounds or nectarthode.
Are stomata passive entry ports?
NO; guard cells perceive Bacterial attack and stomata close within 1hr
What is the gene-for-gene resistance model?
For every resistance gene in the plant, there is a matching gene in the pathogen that determines if it can cause disease.
What is an avirulent gene?
When the plant has evolved to recognise the presence of the pathogen effectors.
What are HR responses in plants?
Hypersensitive responses; limit biotrophic pathogen growth
What is n example of plant HR?
Powdery mildew induces single cells to die on plants with a resistance gene.
How long do resistance genes last?
5 years
