INSECTICIDE MODE OF ACTION by HC120622213814

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									                               INSECTICIDE MODE OF ACTION
                                          Feb 2012
                               Orvin Bontrager, Servi-Tech, Inc.

I. CENTRAL NERVOUS SYSTEM TOXINS
       A. SYNAPTIC TOXINS, act upon neurotransmitters in the synapse
               1. ACETYLCHOLINE ESTERASE INHIBITORS
                      a. ORGANOPHOSPHATES
       Malathion, Ethyl and Methyl Parathion, Penncap M (encapsulated methyl
       parathion), Counter CR, Thimet (phorate), Lorsban 15G and 4E, Diazinon,
       Guthion, Dimethoate, Di-Syston, Imadan from Gowan Company

       Fortress 2.5G (chlorethoxyfos) for rootworm and Counter 20G (terbufos) from AMVAC
       and Rosen’s in Smartbox and Lock and Load boxes.
       Counter Smartbox 20G, from AMVAC. Terbufos 20G will replace the 15G formulation.
       SmartChoice from AMVAC for 2010. Fortress + bifenthrin (a pyrethroid).

       Defco 2.1 G, generic Aztec

       Aztec 2.1G combination of an OP (tebupirimphos) and a pyrethroid (cyfluthrin).

       Cobalt from Dow AgroScience, Lorsban (chlorpyrifos) + a pyrethroid (an isomer of
       Warrior) new for 2008.

       Lorsban Advanced from Dow AgroScience for 2009. New low-odor, water- based
       formulation of chlorpyrifos.
       Lorsban 4E deleted from label for pre-plant and T-band applications for corn in 2010.

       Stallion from FMC- Chlorpyrifos + Mustang Max labeled 2011.

       -First OP’s derived from nerve gas in WWII
       -Non-reversible cholinesterase inhibitors. Inhibits acetylcholine esterase production in
       the body. As a result, this leads to a buildup of acetylcholine, which leads to over
       stimulation of the nervous system.
       -Generally more toxic than the organochlorines but shorter soil residual.
       -Malathion is the safest by far of the OP’s.
       -Highly toxic to mammals and birds.
       -Currently under EPA review
       -Excellent soil and foliar activity
       -Human exposure symptoms: headache, sweating, blurred vision, nausea, cramps,
       tight chest, fatigue, vomiting, diarrhea, twitching, salivation
       -Enter insect through cuticle, orally, or spiracles as vapor, same as carbamates
       -Rootworm beetle tolerant or resistant problems with Penncap control program.
       -Invite EC- from Florida Foods, a cucurbitacin to mix with reduced rates of OP’s and
       carbamates for corn rootworm beetle control.

                      b. CARBAMATES
       Sevin, Furadan 4F (carbofuran), Temik, Lannate, Larvin


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-MOA the same as the OP’s, but reversible cholinesterase inhibitors.
-Most highly water soluble that have led to leaching problems (Temik).
-Human exposure symptoms same as OP’s.
-Breakdown readily an not considered persistent long term.
-Furadan 15G highly toxic to birds and withdrawn from market.
-Furadan 4F post-emerge for rootworm & suppressionof first generation
corn borer, food tolerances have been discontinued by EPA as of Dec 2009. Can’t use
on crops anymore.
-Sevin safe to mammals

        2. RECEPTOR ANTAGONISTS

                a. NEONICOTINOIDS

Gaucho (Imidacloprid), Admire, Merit (Imidacloprid), Assail (Acetamiprid), Crusier,
Platinum, Bestguard, Actara (Thiamethoxam)

-Cruiser (thiamethoxam) from Syngenta, for corn seed treatment.
-Poncho (clothianidin) seed treatment from Bayer. Offers seedling insects and cutworm
control. Poncho 250 for seedling insects and black cutworm. Poncho 1250 for corn
rootworm control.
-Cruiser labeled for soybeans for early aphid and bean leaf beetle control.
-Cruiser MaxxPak- Cruiser + ApronMax fungicide for soybeans seed treatment.
-Cruiser ExtremePak- Cruiser + MaximXL + Apron XL + Dynasty fungicides for corn seed
treatments
-Cruiser ExtremePak CRW- higher Cruiser rate for corn rootworm control
-Calypso (thiacloprid) new from Bayer, use on pome fruit.
-Leverage 2.7 for cotton and soybeans, combination of imidacloprid + cyfluthrin
(Baythroid) from Bayer CropScience.
- Alias 4F (imidacloprid) from MANA for soybeans for aphids, bean leaf beetle,
whiteflies.
-Avicta Complete seed treatment from Syngenta for 2010.
-Cruiser (thiamethoxam) + Avicta (abamectin) for seed insects and parasitic
nematodes.

-Insecticides modeled after natural nicotine
-MOA- irreversible blockage of postsynaptic nicotinergic acetylcholine receptors (blocks
between synapses of nerve cells in insects)
-Systemic action along with contact and stomach action.
-Bind directly to receptor sites on the dendrite
-No mite or nematode activity

        3. GABA (g-aminobutyric acid) ANTAGONISTS

                a. FIPROLES (PHENYL PYRAZOLES)
Regent, Icon, Frontline (fipronil) from BASF



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-Regent discontinued by BASF for field crop use 2012.
-New chemistry and MOA, registered 1996.
-Causes interference of the passage of chloride ions through the GABA regulated
chloride channel and disrupts the central nervous system activity, causing death.
-Low toxicity to mammals, but highly toxic to fish and birds
-Systemic, contact, and stomach activity
-Low water solubility
-No cross resistance of insects with classes of insecticides
-Seed treatments, baits, foliar sprays

                b. SPINOSYN-BASED INSECTICIDES
Tracer from Dow AgroSciences, Success (spinosad)
Entrust from Dow AgroSciences, the same as Tracer, approved for certified organic
production for Lepidoptera larvae in corn.
Delegate WG and Radiant EC – new spinosyns from Dow AgroScience

-MOA- disrupts binding of acetylcholine in nicotinic acetylcholine receptors
-Fermentation-derived products produced by an Actinomycete discovered in a soil
sample.
-Tracer good on corn borer and other Lepidoptera in corn and popcorn, easy on the
beneficials.
-Safe to birds, mammals, fish
-Degrades rapidly in a matter of days, both contact and feeding activity.

B. NERVE AXONAL TOXINS, act upon axon part of the nerve cell

       1. ORGANOCHLORINES (CHLORINATED HYDROCARBONS)
DDT (1940), Dieldrin, Aldrin, Endrin, Lindane, Toxaphene (1947), Chlordane (1945), BHC,
Heptachlor (1949), Mirex, Kelthane, Thiodan, Methoxychlor, Endosulfan (1956)

-Many discontinued due to biomagnification, the accumulation of the chemical in
the body fat of animals.
-Long soil residual because of chlorines in the molecule, most not soluble in water.
-MOA is apparently from disruption of transmission of nerve impulse by the
interference with the sodium- potassium ion balance. Nerve poisons.
-Symptoms of human exposure the same as OP and carbamates
-Enter insect by absorbed through cuticle, orally, or spiracles
-DDT still most widely used insecticide in the world
-Excellent soil activity- rootworms, termites

       2. PYRETHROIDS
Asana XL, Pounce (Ambush), Capture (Brigade, Talstar), Warrior (Karate), Force 3.0 G,
Ammo (Cymbush), Scout, Fury

-Baythroid (cyfluthrin) from Bayer and Mustang Max (zeta-cypermethrin)from FMC for
numerous crops.
-Proshield - corn seed treatment with Force.



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       -Discipline 2 EC- generic bifenthrin for 2004 from AMVAC Chemical Corporation. Other
       generic bifenthrin available for 2005.
       -Capture LFR, FMC’s bifenthrin to mix with liquid fertilizer for in seed slice application at
       planting for rootworm for 2007.
       -Brigade, FMC’S bifenthrin EC for 2007.
       - Fanfare from MANA for 2009, bifenthrin active ingredient.
       -Respect (zeta-cypermethrin) from BASF for 2007. Like Mustang Max
       -Hero from FMC, combination of bifenthrin + Mustang Max for 2008
       -Liquid Force CS closed system by Syngenta for 2008 for corn rootworm control.
       -Endigo ZC from Syngenta for 2009. Warrior + Cruiser for soybeans.

       -MOA as nerve poisons, disrupt the sodium/potassium ion balance along the nerve cell
       wall.
       -Very low mammalian and bird toxicity; however, very toxic to fish and aquatic
       arthropods and honey bees.
       -Human exposure symptoms: nausea, vomiting, hyperactivity, diarrhea, headache, skin
       reactions from addition of cyano group, convulsions, paralysis
       -Low water soluble, do not biomagnify
       -Applied at very low rates (less than 1 oz per acre).
       -Pyrethroids are more toxic with lower temperatures.
       -Selective soil and foliar activity
       -Mimic the naturally occurring Pyrethrum that is found in flower of pyrethrum daisy
       (Chrysanthemum cinerariaefolium).

II. MICROBIAL or BOTANICAL INSECTICIDES

       A. Various BT’S (Bacillus thuringiensis var. kurstaki), Dipel 10G, SG and ES, M-Peril,
       Condor, Full-Back, Javelin

       -Occur naturally in soils
       -Bt protein toxin is the active ingredient, gram positive bacteria that produces
       insecticidal crystal proteins at sporulation.
       -Cry proteins or Cry genes
       -High pH of worm’s gut causes the Bt protein toxin to attach to gut wall and destroys the
       cell walls, allowing the gut to disintegrate. Deactivated in acid of mammalian gut.
       -Granules good on first generation corn borer control, differences in products and
       formulations.

       -Various Bt proteins, Cry I, II, III, IV-X genes for Lepidoptera and Coleoptera, Diptera
       control.
       -YieldGard Cornborer Bt (events Mon 810 and Bt 11, Cry 1Ab); Knockout, NatureGard
       (event 176, Cry 1Ab); Starlink (event CBH 351, Cry 9C).
       -Yieldgard Rootworm Bt (Cry 3Bb1) gene for corn rootworm control in corn, from
       Monsanto. 20% refuge needed.
       -Herculex I, (Cry 1F) Bt gene event in corn that controls corn borer, fall armyworm,
       cutworm, western bean cutworm from Mycogen, Hoegemeyer, Pioneer and other some
       seed companies.
       -Non-genetically altered crop refuges required to slow insect population resistant.


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        -Herculex RW, (Cry 34Ab1, 35Ab1) Bt proteins, from Pioneer, Mycogen and other seed
        companies for 2006.
        -Herculex Xtra (Cry 1F, Cry 34Ab1, 35Ab1)for both above and below ground insect
        control.
        - Agrisure RW (mCry3A) new corn rootworm event from Syngenta for 2007, Agrisure
        CB/LL/RW (Cry 1Ab, mCry3A).
        -Yieldgard VT Triple (Cry 1Ab and Cry3Bb1) new event from Monsanto for 2008,
        rootworm, corn borer and glyphosate resistant corn. Suppression of earworm, fall
        armyworm and stalk borer.
        -Agrisure Vipera from Syngenta for 2010. From sour milk. Multiple modes of action
        event, Vip3A, not a Cry protein. Controls black cutworm, stalk borer, bean cutworm,
        fall armyworm, corn borer, corn earworm


        B.   PYRETHRUM- axonic poison
        C.   ROTENONE- respiratory enzyme inhibitor
        D.   LIMONENE- similar to pyrethrum
        E.   NEEM- disrupts molting, ecdysonem

III. MITOCHONDRIAL TOXINS (PYRROLES)
        Pirate for cotton, Alert for corn. Experimental from BASF.
        -New MOA, oxidation of ADP to ATP blocked in mitochondria within insect cells.
        -Control of mites is excellent.
        -No cross resistance to any insects at this time.

IV. INSECT GROWTH REGULATORS
        A. CHITIN SYNTHESIS INHIBITORS- Dimilin (diflubenzuron)
        - Interferes with an insect’s ability to molt successfully
        - Inhibits the formation of chitin, the hardened component of the insect exoskeleton
        - Very toxic to aquatic insects and arthropods, non-toxic to mammals

        - Intrepid (methoxyfenozide)- new from Dow AgroSciences, Lepidoptera larvae molt
        prematurely. New label for field corn and vegetables. Popcorn label for corn borer,
        western bean cutworm and true armyworm for 2010.

        -Onager (hexythiazox) from Gowan Company for spider mites on corn in western High
        Plains.

        B. LIPID BIOSYNTHESIS INHIBITORS- tetronic acid chemicals
        - Oberon (spiromesifen) from Bayer CropScience. Labeled in 2005. New mode of action.
        For spider mites in corn and whiteflys.
        - Envidor (spirodiclofen) for permanent crops.


V. ANTHRANILIC DIAMIDE CLASS

        A. Altacor/Coragen with rynaxypyr - new from DuPont. Chemical name -
        Chlorantraniliprole


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Prevathon labeled for 2012 on field and seed corn

-Voliam flexi from Syngenta for 2009 on potatoes. Chlorantraniliprole + thiamethoxam
(Cruiser)

- New mode of action, ryanodine receptor agonist. Highly active against a broad
range of lepidopteran larvae and certain other insects, including leafminers by
systemic action. Altacor for cotton and potatoes. Coragen for vegetables.
-Very low mammalian toxcity

B. Belt SC (flubendiamide) from Bayer CropScience for 2009. A phthalic acid diamide.
Labeled on field corn, popcorn, sweet corn, seed corn. Good on lepidopteran larvae.

-Chemistry disrupts the calcium balance in insect muscles, resulting in paralysis and
death.




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