insecticides of novel mode of action in Pakistan and across the Pakistan

1. M.Wasim
PAGF16E46
University college of Agriculture,
university of Sargodha

2. Table contents
• Why we need new chemistry insecticides…?
• Classification of old insecticides
• Classes of new chemistry insecticides
• Future challenge

3. 1. Neo-Nicotinoids
• Synthetic analogue of nicotine
• Drawbacks
• Divides into three groups
a. Chloronicotinyl compounds
 A.Example:
Imidacloprid
 Toxicity
 Acute oral LD50 for rat mg/kg 450
 Acute dermal LD50 mg/kg is >5000 (rats)

4. • It is the first commercial insecticide of this group
which inhibits nicotinic acetylcholine by binding with
nicotinic acetylcholine receptor
• It acts as systemic insecticide and used to control
sucking pest
 Trade name: Confidor

5.  Toxicity
Acute oral LD50 for rat mg/kg 146-217
Acute dermal LD50 mg/kg is >2000(rats)

6. • Exhibits a systemic translaminar action
• It has a novel mechanism of action on the insect
nervous systems by acting as an agonist to nAch
• it also has ovicidal, adulticidal and larvicidal.
 Trade name
Wapkil

7. example: Thiamethoxam
 Toxicity
• Acute oral LD50 for rat mg/kg 1563
• Acute dermal LD50 kg/kg is >2000 (rat)
 Trade name: Evident ®

8.  Broad spectrum insecticide
 Quickly absorbed by plant and transported to all parts
of plant including pollen
 Entre into insect body through tracheal system, feeding
or by contact action
 interfering with nicotinic acetylcholine receptors in the
central nervous system and eventually paralyzes the
muscles of the insects.

9.  Example: Dinotefuran
 Toxicity
• Acute oral LD50 for rat mg/kg 15
• Acute dermal LD50 mg/kg is 5000 (rabbit)

10. • The insecticidal action is due to activation of
nicotinic acetylcholine receptors.
• Also effect nAch
• These insecticides are theoretically less toxic
to mammals due to a lower affinity for
vertebrate nicotinic receptors
• Used against aphid,thrips, leafminers
 Trade name:
Token®

11.  Example: Fipronil
 Toxicity
Highly toxic to mammals,

12.  Fipronil is a broad-spectrum insecticide that disrupts
the insect central nervous system by blocking GABA-
gated chloride channels
 Used against fleas, ticks, termite, thrips, rootwroms
 Trade name:
Regent®

13.  Example
Indoxacarb
 Toxicity
 Acute oral LD50 for rat mg/kg 258-1723
 Acute dermal LD50 mg/kg is >5000 (rabbit)
 Effective against lepidopteran pest

14.  It blocks the movements of sodium ions in certain
nerve cells, which results in paralysis and death of the
affected insects
 Trade name
Avaunt®

15.  Example
Chlorfenapyr
Toxicity
 Acute oral LD50 for rat mg/kg441-1152
 Acute dermal LD50 mg/kg is 2000(rabbit)

16.  Inhibitor of oxidative phosphorylation, preventing the
formation of the crucial energy molecule adenosine
triphosphate (ATP)
 Trade name: Intrepid®

17. Example: Diafenthiuron
Toxicity:
 Acute oral LD50 for rat mg/kg 2068
 Acute dermal LD50 is mg/kg 2000(rats)

18. • Inhibitors of oxidative phosphorylation, disruptors
• of ATP formation (inhibitors of ATP synthase)
• Extensively used against sucking insect pest whiteflies ,
aphid, jassid
• Powerful toxicant for controlling sweatpotato whitefly
 Trade name: Polo®

19.  Example
Bifenazate
 Trade Name:
Floramite®
 Mode of action
mode of action is unclear, mostly used against wide
range of mite

20.  Example
Flufenoxuron
 Toxicity
 low mammlian toxicity

21.  Mode of action Insect and acarid growth regulator
with contact and stomach action.
 Uses to control immature stage of many phyto-phagous
mites.
 Trade name
Cascade®

22.  These are natural toxicant and insecticide derived from
plant e.g. . Tobacco, pyrethrum, derris.
1.Pyrethrum

23.  Acute oral LD50 for rat mg/kg 1030-2370
 Acute dermal LD50 mg/kg is 5000 (rabbit)
Mode of action
• Axonic, poisonare those that in some way affect the
electrical impulse transmission along the axons
• Acts as contact poison
Trade name:
Alfadex, kicker

24.  Extracted from tobacco
 Effective for mostly insect but mostly used against
caterpillar and aphid

25.  Acute oral LD50 for rat mg/kg 50-60
 Acute dermal LD50 mg/kg is 50(rabbit)
 Mode of action
Nicotine mimics acetylcholine (ACh) at the
neuromuscular (nerve/muscle) junction in mammals,
and results in twitching, convulsions, and death
Trade name:
Nico Soap

26.  Rotenoids are produced in the roots of two genera of the
legume family: Derris
 Toxicity
 Acute oral LD50 for rat mg/kg 132-1500
 Acute dermal LD50 mg/kg is > 5000(rabbit)
 Mode of action
Rotenone is a respiratory enzyme inhibitor, acting
between NAD+ (a coenzyme involved in oxidation and
reduction in metabolic pathways) and coenzyme Q (a
respiratory enzyme responsible for carrying electrons in
some electron transport chains), resulting in failure of the
respiratory functions.

27.  Neem oil extracts are extracted from the seeds of the
neem tree and contain the active ingredient
azadirachtin

28.  Acute oral LD50 for rat mg/kg >5000
 Acute dermal LD50 mg/kg is > >2000(rabbit)
Mode of action
Azadirachtin disrupts molting by inhibiting
biosynthesis or metabolism of ecdysone
 Trade name
Align,Neemix

29. 1. Abamectin
Source : Source: Streptomyces avermitili
 Trade name: Agri-Mek

30. • Acute oral LD50 for rat mg/kg 10
• Acute dermal LD50 mg/kg is > 2000 (rabbit)
Mode of action
• They stimulate the gamma-aminobutyric acid
(GABA) system, a chemical “transmitter” produced
at nerve endings, which inhibits both nerve to nerve
and nerve to muscle communication.
• it is insecticide, acaricide and nematicide

32.  Acute oral LD50 for rat mg/kg 76-79
 Acute dermal LD50 mg/kg for rabbits >2000
Mode of action
They stimulate the gamma-aminobutyric acid (GABA)
system, a chemical “transmitter” produced at nerve
endings, which inhibits both nerve to nerve and nerve
to muscle communication
Trade name: Proclaim®

33.  Source: Saccharopolyspora
 Spinosad

34.  Acute oral LD50 for rat mg/kg3783-75000
 Acute dermal LD50 mg/kg for rabbits>2000
 Mode of action
The spinosad have a novel mode of action, primarily
targeting binding sites on nicotinic acetylcholine
receptors (nAChRs) of the insect nervous system
 Trade name : SpinTor

35.  Bacillus thuringiensis
 Mainly affect three oders lepidoptera, diptera and
coleoptera
 Mode of action
 Bacteria produces crystalline protein ,eaten by
caterpillar , then they attach to body gut wall receptor
of caterpillar and stop the feeding
 With in hours gut wall dissolved and normal bacteria
entre to gut body where the toxin dissolve

37.  Transgenic plant produces BT.endotoxins as
systemic insecticide
 Available as cotton, tomato and potato
showing resistant to lepidopteron pest
 Safe to environment
 No harm to beneficial insect

38.  Metarhizium anisopliae
conidia spore Different cultures of M. anisopliae cockroach killed by m.anisopliae
M.anisopliae

39. • Acute oral LD50 for rat mg/kg>5050
• Acute dermal LD50 mg/kg for rabbits>2020
 Mode of action
When these mitotic spores of the fungus come into
contact with the body of an insect host, they germinate
and the hyphae that emerge penetrate the cuticle and
grow rapidly ,eventually cause death

40.  To develop more and more new molecules having
Low toxicity to mammals, high efficacy and quick
knockdown effect, less leaching potential and less harmful to
benificial insect
 More biotechnological innovations to be directed in transgenic
plants etc.
 More innovative technology to be developed in application of
pesticides
 Minimization of residue load in ecosystem
 More emphasis shall be given in bio-control agents
 Research emphasis shall be given in innovations of more plant
derived bio-pesticides

41.  Principles of insect toxicology
 Insecticides with Novel Modes of Action: Mechanisms
and Application
 http://www.interesjournals.org/full-articles/mode-of-
action-of-pesticides-and-the-novel-trends-a-critical-
review.pdf?view=inline