Various recent method of pest control viz genetic, anti-feedents etc.

1. RECENT METHODS OF PEST CONTROL
MD.MAHTAB RASHID
BPSAC/21/2012-2013
B.Sc.(Ag)
4th Semester

2. Recent methods of pest control
includes following agents
A. Anti-feedants
B. Insect Attractants
C. Insect Repellants
D. Genetic Control/Autocidal Control
E. Insect Growth Regulators

3. A. ANTIFEEDANTS
 These are the chemical substances that inhibit
feeding of insects when applied on the foliage
without impairing their appetite and gustatory
receptors or driving them away from the food.
 They are also called Gustatory repellants/ Feeding
deterrents / Rejectants.
 Since insects do not feed on treated surface, they
die due to starvation.

4. MODE OF ACTION
 They inhibit gustatory (taste) receptors of the
mouth parts

5. GROUPS OF ANTIFEEDANTS
A. Triazines
eg:- Acetanilide
B. Organotins :- Compounds having tin
eg:-Triphenyl tin acetate
C. Carbamates :- Sub-lethal doses of
thiocarbamates
eg:- Baygon
D. Botanicals :- Anti-feedants from non-host
plants
∙Pyrethrum- From C. cinerarifolium
.Neem
.Apple factor
.Solanum alkaoids- Leptine, Tomatine & Solanine

6. ADVANTAGES DISAADVANTAGES
 Affects plant feeders
but safe to N.E.
 Pests are not killed
immediately so N.E.
can feed on them
 No phytotoxicity
 No pollution
 Not effective for
sucking pests
 Not effective as sole
control measure

7. B. INSECTS REPELLENTS
 Chemicals which cause insects to move away
from their source are referred to as repellents (or)
Chemically that prevent insect damage to plants
(or) animals by rendering them unattractive,
unpalatable (or) offensive are called repellents.
 Mode of Action:- Influences both gustatory &
olfactory receptors.

8. TYPES OF REPELLENTS
Physical repellents
 Contact stimulus
repellents
eg:- Wax or Oil
 Auditory repellents
amplified sounds
 Barrier repellants
eg:-Tar bands or
Mosquito nets
 Visual repellents
eg:- Yellow light
 Feeing repellants
eg:-Antifeedants
Chemical repellents
 Plant origin eg:-
Oils from Citronella,
Camphor, Cedarwood
& Lemon-grass
 Synthetic repellents
eg:-Dimethyl pthalate,
Napthalene, Bordeaux
mixture & Smoke

9. C. INSECTS ATTARACTANTS
 Chemicals that cause insects to make oriented
movements towards their source are called insect
attractants.
 Mode of Action:- It influences both gustatory and
olfactory receptors

10. TYPES OF ATTARACTANTS
1. Pheromones:-Chemical that is secreted into the external
environment by an animal and that elicits a specific response
in a receiving individual of the same species.
2. Food Lures:-These are Chemicals present in plant and animal
hosts that attract (lure) insects for feeding. They stimulate
olfactory receptors.
3. Oviposition Lures:-These are chemicals that govern the
selection of suitable sites for oviposition by the adult female
eg:-Corn attaractants for H. armigera
4. Poison Baits:-Poison baits are a mixture of food lures and
insecticides. The effort is made to make the bait more
attractive to insects than their natural food and also a smaller
quantity should be able to attract the largest number of
insects.

11. ADVANTAGES
DISADVANTAGES
 Target specific
 Doesn’t disrupt eco-
system
 Can be used for
mass trapping
 Do not cause
environmental
pollution
 Insects can always
find untreated hosts
 It is not a sole source
of insect control

12. PHEROMONES
 Semiochemicals:- They are chemicals that mediate
communication between organisms.
 It is classified into two groups:-
i. Pheromones:- Intra-specific
ii. Allelo-chemicals:- Inter-specific
--Pheromones are also called Ectohormones.
--The term “pheromone” was given by Karlson and
Butenandt in 1959 when they identified it in Silkworm
moth.

13. CLASSIFICATION OF
PHEROMONES
 Primer pheromones:- A chain of physiological changes
is triggered off in the receiving animal. They act on
gustatory receptors.
eg:-Caste discrimination & reproduction in social
insects.
 Releaser pheromone:-An immediate and reversible
behavioural change is produced in the receiving
animal.
i. Sex Pheromone
ii. Aggregation Pheromones
iii. Trail Pheromones

14.  Aphrodisiacs:- These are substances that aid in courtship
of the insects after two sexes are brought together. In many
cases, male produce aphrodisiacs.
 Calling position:- The posture shown by the female during
the pheromone release.
 Mono-component pheromone system:- If a pheromone
consists of only one chemical compound.
 Multi-component pheromone system:- If a pheromone
consists of more than one chemical compounds.
 Use of Sex pheromones in Pest management
i. Monitoring
ii. Mass trapping
iii. Confusion or Decoy method

15. D. GENETIC INSECT
CONTROL/AUTOCIDAL CONTROL
A) Induced Sterility
i) Sterile male release technique: When a sterile male mates with
normal female there will be no progeny.
-This theory of Male Sterile Technique was conceived by
E.F. Knipling as early as 1937.
ii) Aspermia: Inactivation of sperms.
iii) Infecundity: Sterile eggs by dominant lethal mutation.
B) Cytoplasmic Incompatiblity: Sterility is due to a cytoplasmic
factor transmitted through the egg, which kills the sperm of
incompatible male after its entry into the egg.

16. C) Hybrid Sterility: In some insect cross-types or races which
produce fertile females but sterile males among progeny.
D) Population replacement: The ability of disease
transmission
of vectors i.e. replacement of specific vector populations
can
as well be changed by genetic methods.
E) Autosterilization: Sterilization of native insects in their
natural environment by using chemosterilants along with
the species specific attatractants / lures/ bait traps.
-Bonus effect: The sterile males mates with the normal
females thus reduces reproductivity.

17. METHODS OF STERILIZATION
A. Chemosterilants
i. Alkalyting agents: They inhibit nucleic acid
synthesis, inhibits gonad development & produce
mutagenic effects.
Eg:- TEPA, Chloro ethylamine etc.
ii. Antimetabolites: Chemicals with structural
similarity with biological substances.
Eg:- 5-Fluororacil, Amethopterin etc.
B. Irradiations: It is done by exposing the insects to X-
rays or neutrons emitted from Cobalt.

18. E. INSECT GROWTH
REGULATORS
 IGRs are compounds which interfares with the
growth, development and metamorphosis of
insects.

19. TYPES
1.Ecdysone or Moulting Hormone (MH):Synthetic
analogues of ecdysones are called ecdysoids
- It causes defective cuticle formation.
2. Juvenoids: The possibility that JH analogs may have
potential as insect control was first recognized by
Williams & Slama (1966). The compounds showing JH
activity, ‘Juvenoids’.
-They found it in paper made of Balsam fir tree.

20. 3.Anti JH or Precocenes: Precocenes are the compounds
which would antagonize the JH activity and de-arrange the
insect development. These compounds induce the
precocious metamorphosis of immature insects.
Precocenes affect insect diapause, reproduction and
behaviour. These compounds first extracted from the plant
Ageratum houstonium.
4.Chitin synthesis inhibitors: Chitin synthesis inhibitors disrupt
molting by blocking the formation of chitin, the building block
of insect exoskeleton. Without the ability to synthesize chitin,
molting is incomplete, resulting in malformed insects that soon
die. It suppresses egg-laying and causes egg sterility in treated
adults through secondary hormonal activity
Eg:-Diflubenzuron, Flufenoxuron etc.

21. THANXXXXX FOR HAVING
PATIENCE WITH ME….