Naming Fungicides Lecture Flashcards
The mode of action that is based on toxins relationship with the fungus :
Biochemical mode of action
The Mode of Action that is based on toxins relationship with the plant :
Topical mode of action
Define: Biochemical mode of action
Based on toxins relationship with the fungus
Define Topical mode of action :
Based on toxins relationship with the plant
The Mode Of Action is based on what?
Phytomobility - how the a.i. moves within the plant
Mode of action is also broadly classified as _________ or ________.
Contacts or Penetrants
Why do penetrant fungicides take longer to work than contacts?
They have to get indside the plant to begin working
Where do penetrant fungicides affect fungi?
At metabolic sites
What are some key traits for a Localized Penetrant?
-It is absorbed, but doesn’t move around -Sticks to the cuticle
What are are some key traits for Acropetal Penetrants?
They enter the plant and move between the cells along the Xylem and go UP ONLY.
What are some key traits for a Systemic Penetrant?
Is it absorbed into the plant cells and follows the transport of sugars in the phloem. It move both UP AND DOWN.
Compare Biochemical MOA and Topical MOA
Biochemical MOA is based on the toxin’s relationship with the fungus and Topical MOA is based on the toxin’s relationship with the plant
BIOCHEMICAL MOA: –Compare Multi-Site Toxins and Site-Specific Toxins
Multi-site toxins affect multiple metabolic sites and usually kill the fungus, might kill the plant and have little chance of resistance Site specific toxins affect a single metabolic site, most are fungistatic (stop fungal growth) but don’t kill the fungus. High likelyhood of resistance
Define Monogenic resistance:
Fungi only need to change a sngle major gene to become resistant so resistance development is rapid
Define Polygenic resistance:
Fungi need to chance several major genes to become resistant so resistance development is gradual.
