insecticides ppt

1. Insecticides

2. Insecticides
• An insecticide is a pesticide used to
kill insects.
• They include ovicides and larvicides
used against the eggs and larvae of
insects respectively.
• Insecticides are used in agriculture,
medicine, industry and the
household.

3. classification of insecticides
• Systemic insecticides - Insects ingest the
insecticide while feeding on the plants.
• Contact insecticides are toxic to insects
brought into direct contact.
• Natural insecticides-They are extracts
made by plants as defenses against
insects.
• Eg.-Nicotine pyrethrum and neem based
insecticides

4. • Plant-incorporated protectants
(PIPs)-They are insecticidal
substances produced by plants after
genetic modification.
• a gene that codes for a specific
Baccilus thuringiensis biocidal
protein is introduced into a crop
plant's genetic material.
• Then, the plant manufactures the
protein.

5. • Inorganic insecticides-They are
manufactured with metals like
arsenates, copper and fluorine
,sulfur compounds.
• Organic insecticides-They are
synthetic chemicals

6. Organochlorides
• They are the best known insecticides
• Eg.-DDT, was made by the Swiss Scientist Paul
Müller. for which he was awarded the Nobel
Prize for Physiology or Medicine in 1948.
• Later chlorinated hydrocarbons were made
• DDT works by opening the sodium channels in
the nerve cells of the insect.
• Examples- Aldrin, Endosulfan
• Endrin, Hexachlorobenzene
• Lindane (gamma-hexachlorocyclohexane)

7. Organophosphates
• These act by binding to acetylcholinesterase
and other cholinesterases.
• This results in disruption of nerve impulses,
killing the insect or interfering with its ability
to carry on normal functions.
• Organophosphate insecticides and chemical
warfare nerve agents (such as sarin, tabun,
soman and VX) work in the same way.
• Eg.-Dichlorvos (DDVP),Dicrotophos,
• Malathion,Monocrotophos

8. Carbamates
• Carbamate insecticides have similar toxic
mechanisms to organophosphates,
• but have a much shorter duration of action
and are thus somewhat less toxic.
• Eg.-Aldicarb
• Bendiocarb
• Carbofuran
• Carbaryl

9. Pyrethroids
• pyrethroid pesticides mimic the insecticidal
activity of the natural compound pyrethrum .
• These are nonpersistent sodium channel
modulators, and are much less acutely toxic
than organophosphates and carbamates.
• Compounds in this group are often applied
against household pests.
• Examples-Allethrin,Cypermethrin
• Deltamethrin,Permethrin

10. Neonicotinoids
• Neonicotinoids are synthetic analogues of the
natural insecticide nicotine .
• These are nicotinic acetylcholine receptor
agonists.
• They are applied as sprays, drenches, seed
and soil treatments—instead of
organophosphates and carbamates.
• Treated insects exhibit leg tremors, rapid wing
motion, stylet withdrawal (aphids),
disoriented movement, paralysis and death.
• Example-Imidacloprid .

11. Ryanoids
• Ryanoids are synthetic chemicals.
• They bind to calcium channels in
cardiac and skeletal muscle,
blocking nervous transmission.
• Example-Rynaxypyr,

12. Insect Growth Regulators
• Insect growth regulator is a chemical which
inhibit chitin (exoskeleton) biosynthesis in
insects.Eg.- benzoylphenyl ureas
• Diflubenzuron is used primarily to control
caterpillars which are pests.
• The most successful insecticides in this class are
the juvenoids (juvenile hormone analogues). Eg.
Methoprene
• Controls mosquitoes, several fly species, and
fleas cockroaches and white flies.

13. Biological insecticides
• Insecticides are produced by bacterium.
• Toxins produced by different strains of this
bacterium are used as larvicide against
caterpillars, beetles, and mosquitoes.
• Eg.- Spinosad.
• As these toxins have little effect on other
organisms they are considered more
environmentally friendly than synthetic
pesticides.
• The toxin from B. thuringiensis (Bt toxin) has
been incorporated directly into plants through
the use of genetic engineering.

14. Antifeedants
• Many plants have substances, like
polygodial, which prevent insects
from eating, but do not kill them
directly.
• The insect often remains nearby,
where it dies of starvation.
• Since antifeedants are nontoxic, they
would be ideal as insecticides in
agriculture.

15. Environmental effects
Effects on nontarget species
• Some insecticides kill other creatures in
addition to those they are intended to kill.
• For example, birds may be poisoned when
they eat food that was recently sprayed with
insecticides or
• when they mistake insecticide granules on the
ground for food and eat it.[6]
• Sprayed insecticides may drift from the area
to which it is applied and into wildlife areas,
especially when it is sprayed aerially.[6]

16. Thank you
Dr.Muneer kanha,M.D.
GMC,GUNTUR