Transcript Insecticides

Insecticides
PESTICIDE CHARACTERISTICS
Age
 Best used when mixed, don’t store
after mixing
PESTICIDE CHARACTERISTICS
Thatch
 Excessive thatch (>1/2”) binds
insecticide
PESTICIDE CHARACTERISTICS
UV degradation
 Breaks chemical bonds
 Biologicals most susceptible
PESTICIDE CHARACTERISTICS
pH impact
 Neutral pH is best
PESTICIDE CHARACTERISTICS
Microbial degradation
 Bacteria and fungi feed on organic
portion of pesticide
 Can break down within hours
GENERAL CLASSIFICATION
Stomach poisons
 Enter insect through the gut when
eaten
GENERAL CLASSIFICATION
Systemic poisons
 Translocated within plants
 Insects exposed when feeding
 Most effective on piercing-sucking
insects

Receive greater dose
GENERAL CLASSIFICATION
Contact poisons
 Enter body when insect walks over
treated surface
GENERAL CLASSIFICATION
Insect Growth Regulator (IGR)
 Interferes with normal growth
 Prevents molting (juvenile
hormones)
 Very safe, delayed effect
GENERAL CLASSIFICATION
Biorational (Biological)
 Beneficial fungi, nematodes or
bacteria
MODE OF ACTION
Nerve poisons: most
conventional
insecticides
a) Narcotics

Physical action in
nervous system
MODE OF ACTION
Nerve poisons
b) Synaptic
 Interrupt synaptic transmission of
nervous system
 Synapse (gap) is the junction
between a neuron and another cell
(muscle, gland, etc)
MODE OF ACTION
Nerve poisons
b) Synaptic
 In central nervous system,
acetylcholine transmits an impulse
across synapse to next cell
 Chemicals tie up acetylcholine and
cause malfunction
MODE OF ACTION
Muscle poisons
 Disrupting muscle membrane
MODE OF ACTION
Physical toxicants
 Horticultural Oil

Clog the spiracles that breathe
MODE OF ACTION
Physical toxicants
 Insecticidal soap

Strips cuticle and dehydrates insect
MODE OF ACTION
Physical toxicants
Diatomaceous earth
 Crushed fossils
 Cut insects walking over it
 Dehydrate
SOURCE CLASSIFICATION
Inorganic: lack carbon
 Organic: possess carbon

Natural are produced from natural
substances: botanicals and oils
 Synthetics are manmade

MAJOR CLASSES OF ACTIVE
INGREDIENTS
Pesticide rotation
 Rotate chemical classes


Change mode of action (MOA)
http://www.irac-online.org/
MAJOR CLASSES OF ACTIVE
INGREDIENTS
ORGANOPHOSPHATES (OP)
 Unstable in light
 Was most widely used insecticides
MAJOR CLASSES OF ACTIVE
INGREDIENTS
ORGANOPHOSPHATES (OP)
Malathion,
Diazinon and Chlorpyrifos (Dursban)

Cancelled
MAJOR CLASSES OF ACTIVE
INGREDIENTS
CARBAMATES
 Low persistence in environment
 Noted toxicity to pollinators
MAJOR CLASSES OF ACTIVE
INGREDIENTS
CARBAMATES
Carbaryl
 Greatest use is
fruit production
 Controls insects
and fruit-thinning
agent
MAJOR CLASSES OF ACTIVE
INGREDIENTS
CARBAMATES
Carbofuran (cancelled)
 Ineffective when used continuously
 Microorganisms quickly degrade
MAJOR CLASSES OF ACTIVE
INGREDIENTS
CHLORINATED HYDROCARBONS
 Most persistent insecticide class
MAJOR CLASSES OF ACTIVE
INGREDIENTS
CHLORINATED HYDROCARBONS
DDT
Cancelled in US in 1973
Extremely stable
 Resistant to MO, heat, and UV light
Fat solubility
 Other classes broken down in animals by
enzymes
MAJOR CLASSES OF ACTIVE
INGREDIENTS
CHLORINATED HYDROCARBONS
DDT: 2 characteristics for cancellation
1. Stability allows more to be taken up by
animals
2. Accumulates in body fat

Found traces in milk fat and in human body fat
MAJOR CLASSES OF ACTIVE
INGREDIENTS
CHLORINATED HYDROCARBONS
DDT
Biomagnification
 As predators consume organisms,
DDT accumulates in fat of predator
 Thin egg shells, reproductive failure…
MAJOR CLASSES OF ACTIVE
INGREDIENTS
BOTANICALS
 Derived directly from plants
 Organic gardening
 Considered safer, some exceptions
 Most are expensive and impractical
on commercial scale
MAJOR CLASSES OF ACTIVE
INGREDIENTS
BOTANICALS
Pyrethrum
 Extracted from Chrysanthemum
 Wide spectrum and rapid knockdown
 Breaks down rapidly in sunlight
MAJOR CLASSES OF ACTIVE
INGREDIENTS
BOTANICALS
Rotenone
 Second most used botanical
 Extremely toxic to fish
MAJOR CLASSES OF ACTIVE
INGREDIENTS
BOTANICALS
Rotenone
 New research released in the United
States on Monday shows a link
between the use of two pesticides,
rotenone and paraquat, and
Parkinson's disease. People who used
either pesticide developed Parkinson's
disease approximately 2.5 times more
often than non-users.
MAJOR CLASSES OF ACTIVE
INGREDIENTS
BOTANICALS
Neem
 Oil from neem tree
 Primarily repellent
 Also medicinal and toothpaste
 http://www.azasol.com/
MAJOR CLASSES OF ACTIVE
INGREDIENTS
PYRETHROIDS (SYNTHETIC)
 Replacing many older insecticides:
effective and safe
 Synthetic pyrethrum
MAJOR CLASSES OF ACTIVE
INGREDIENTS
PYRETHROIDS (SYNTHETIC)
Permethrin
 High toxicity at low rates
 Quick knockdown
 More stable
 Permethrin, Cyfluthrin, Deltamethrin
MAJOR CLASSES OF ACTIVE
INGREDIENTS
PHENYL PYRAZOLES
 Low mammalian toxicity
 Very effective
 Fipronil, season long control of ants
MAJOR CLASSES OF ACTIVE
INGREDIENTS
CHLORONICOTINYLS
 Translocates within plant
 Merit is absorbed through
roots
Suspected in CCD (bees)
 Banned in Canada

Colony Collapse Disorder
(CCD)
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Adult bees fly off to die
Causes include parasites, viruses,
bacteria, poor nutrition and pesticides
No proof of cell tower
MAJOR CLASSES OF ACTIVE
INGREDIENTS
BIORATIONAL (Biological)
 Not substitute for conventional
insecticides
 More scouting and repeat applications
MAJOR CLASSES OF ACTIVE
INGREDIENTS
BIORATIONAL (Biological)
Bt (Bacillus thurigiensis)
 Protein produced by Bt that damages
gut
 Death in couple days
MAJOR CLASSES OF ACTIVE
INGREDIENTS
BIORATIONAL (Biological)
Bt (Bacillus thurigiensis)
Varieties have specific host
 Var. kurstaki kills caterpillars (Dipel)
Genetically modified corn contains
protein
 Monarch butterflies?

MAJOR CLASSES OF ACTIVE
INGREDIENTS
BIORATIONAL (Biological)
Bt (Bacillus thurigiensis)
 Var. israliensis kills mosquitoes
MAJOR CLASSES OF ACTIVE
INGREDIENTS
BIORATIONAL (Biological)
Spinosad
 Derived from bacterium
 Effective flea control