Fungicides

Fungicides
Fungicide Categories
• Contact – work on leaf & stem surface to prevent penetration by fungus
• Systemic – are absorbed into plant tissue and are translocated (primarily in xylem)
• Local systemic – absorbed but only move a short distance, don’t move in vascular tissue
• Mesostemic – new category strongly attracted to plant surface and are absorbed by waxy layers
Comparison of fungicide categories Contact Systemic
• Protective
• Not translocated
• New growth is not protected
• Typically for foliar diseases only
• Broad spectrum
• Little possibility of resistance developing
• Typically not used for root pathogens
• Protective & curative
• Translocated • New growth is protected
• For foliar and root diseases
• Specific mode of action
• More possibility of resistance developing
• Effective on root pathogens
Fungicide Families
•
•
•
•
•
•
Aromatic hydrocarbons
Benzimidazole
Dicarboximide
DMI (demethylation inhibitors)
Ethylenebisdithiocarbamate (EBDC)
Strobilurins
Fungicide families
• Aromatic hydrocarbon
– Contact, protective
– Destroy fungal membranes
– High volitility
• Examples
– Chloroneb (Terraneb)
– Ethazol (Koban, Terrazole)
– PCNB pentachloronitrobenzene
(Terrachlor, Turcide)
• Benzimidazole
–
–
–
–
Systemic, curative, protective
Inhibit cell wall formation
Primarily xylem movement
Translocates in xylem
• Examples
– Benomyl (Tersan 1991, Benelate
– Thiophanate methyl (Fungo)
Fungicide families
• Dicarboximide
– Contact/local systemic
– Interfere with DNA synthesis
– Don’t move in xylem or phloem
• Examples – Iprodione (Chipco 26019)
– Vinclozolin (Vorlan)
• DMI (demethylation inhibitors)
– Systemic, curative & protective
– Inhibits ergosterol biosynthesis
– DON’T APPLY ON BENT OR BERMUDA GREENS ABOVE 90 degrees F
• Examples
–
–
–
–
Fenarimol (Rubigan)
Propiconazol (Banner)
Triadimefon (Bayleton)
Others :Eagle, Tourney, Trinity, and Triton
Fungicide families
• EBDC
Ethylene bisdithiocarbamate
– Contact, protective
– Multiple site mode of action
– Broad spectrum
• Examples
– Maneb (Stoller)
– Maneb+zinc (Diathane M‐45)
– Mancozeb (Tersan LSR)
• Strobilurins
– Systemic, curative
– Quinone inside inhibitor (QiI)
– Moves in xylem
• Examples
–
–
–
–
–
Flutolanil (Prostar)
Azoxystrobin (Heritage)
Trifloxystrobin (Compass)
Tebucanozol (Torque)
Fluoxastrobin (Disarm)
Fungicide Families
• Triazine
– Contact,protective
– Broad spectrum
– Inhibits spores
• Example
– Anilazine (Dyrene)
• Benzonitrile
– Contact, protective
– Broad spectrum
– Inhibits glutathione
• Example
– Chlorothalonil (Daconil)
• Mixtures
– A number of products are available that are mixtures of two chemistries
• Examples
– Azoxystrobin + propiconazole
(Headway)
– Chlorothalonil + fluoxastrobin
(Disarm C)
Pythium fungicides
• Aromatic hydrocarbons
– Discussed on previous slide
– Contact, protective
• Ones that work on pythium
– Chloroneb (Terraneb)
– Ethazol (Koban, Terrazole)
• Carbamate
– Local systemic, degrades quickly in plant, some curative effect
– Inhibits sporulation
– Moves short distance in xylem
• Examples
– Propamocarb (Banol, Proplant )
– Stellar (home lawns, propamocarb + fluopicolide
Pythium fungicides
• Phenylamide
– Systemic, curative
– Inhibit nucleic acid systhesis
– Kills hyphae inside plant thus often used with contact fungicide
– Moves in xylem
• Examples
– Metalaxyl (Subdue, Apron ‐
seed treatment)
• Phosphonate
– Systemic, protective, weak curative
– Moves in xylem & phloem
– Fosetyl‐Al Common seed treatment
• Examples
– Fosetyl‐Al (Aliette, Autogragh, Prodigy, Signature)
– Phosphoric acid (Alude, Magellan, Vital)

Download Report