Insect pheraomones what are way of attractant of insect

1. INSECT PHEROMONES
Dr. Basavarajaiah S. M.
Assistant Professor and Coordinator
PG Department of Chemistry
Vijaya College, Bengaluru-560004.
drsmbasu@gmail.com

2. Contents
Communication in Insects.
Classification of Semiochemicals.
Introduction to Insect Pheromones.
Uses of Insect Pheromones.
Synthesis of Insect Pheromones.
Use of pheromones in insect pest management.

3. COMMUNICATION IN INSECTS
Insects communicate both with organisms of the
same species (intraspecific communication) and
directly or indirectly with organisms of other species
(interspecific communication) for many reasons:
Reproduction.
Identify .
To warn other organisms.
To localize sources of recourses.
As an alert signal or defend territory.

4. Tactile communication: “The touch”
Chemical communication: “smell and taste”
Visual communication: “The sight”
Auditory communication: “the hearing” or Acoustic
communication
Insects use almost all senses to communicate.
Along this section, we’ll analyze one by one all
communication systems that insects developed
through the “five sense”, just like some of the
flashiest examples.

5. Tactile communication: “The touch”
“Tandem running”: Follow the leader
Example; Ants
 Dancing bees
Example; Honey bee
Chemical communication: “smell and taste”
In this type of communication, the emitter scatters
chemical substances at the environment which are
detected by other organisms.
Pheromones (for finding a mate),
Allelochemicals (as alarm signals, as a defensive
system…)

6. Visual communication: “The sight”
Visual communication in insects takes place by
two main systems:
Body color patterns and
Light signals (Bioluminescence).
Auditory communication: “the hearing”
Insects emit a wide variety of sounds in different
frequencies, amplitude and periodicity, and each
species has a very well defined pattern. In fact, only
by registering and analyzing insect’s sounds we can
identify the species that has emitted them.

7. SEMIOCHEMICALS
A semiochemical, from the Greek semeion, meaning
"signal", is a chemical substance or mixture released
by an organism that affects the behaviors of other
individuals.
Semiochemical communication can be divided into
two broad classes: communication between
individuals of the same species (intraspecific) or
communication between different species
(interspecific).

9. INTRODUCTION TO INSECT PHEROMONES
A pheromone is a secreted or excreted chemical factor that triggers a
social response in members of the same species.
Pheromones are chemicals capable of acting like hormones outside
the body of the secreting individual, to impact the behavior of the
receiving individuals.
There are alarm pheromones, food trail pheromones, sex
pheromones, and many others that affect behavior or physiology.
Primer pheromones trigger a change of developmental events (in
which they differ from all the other pheromones, which trigger a change
in behavior).
Releaser pheromones are pheromones that cause an alteration in the
behavior of the recipient.

10. Aggregation
Aggregation pheromones function in mate selection, overcoming
host resistance by mass attack, and defense against predators.
A group of individuals at one location is referred to as an
aggregation, whether consisting of one sex or both sexes.
Male-produced sex attractants have been called aggregation
pheromones, because they usually result in the arrival of both
sexes at a calling site and increase the density of conspecifics
surrounding the pheromone source.

11. Trail Pheromone
Social insects commonly use trail pheromones. For
example, ants mark their paths with pheromones consisting of
volatile hydrocarbons.
Certain ants lay down an initial trail of pheromones as they
return to the nest with food. This trail attracts other ants and
serves as a guide.
As long as the food source remains available, visiting ants will
continuously renew the pheromone trail.
The pheromone requires continuous renewal because it
evaporates quickly.

12. Sex Pheromones
Sex pheromones indicate the availability of the female for
breeding.
Male animals may also emit pheromones that convey
information about their species and genotype.
Territorial Pheromones
Laid down in the environment, territorial pheromones mark the
boundaries and identity of an organism's territory.
In cats and dogs, these hormones are present in the urine,
which they deposit on landmarks serving to mark the perimeter of
the claimed territory.

13. Epideictic Pheromones
Epideictic pheromones are different from territory pheromones,
when it comes to insects.
Fabre observed and noted how "females who lay their eggs in
these fruits deposit these mysterious substances in the vicinity of
their clutch to signal to other females of the same species they
should clutch elsewhere."
It may be helpful to note that the word epideictic, having to do
with display or show (from the Greek 'deixis'), has a different but
related meaning in rhetoric, the human art of persuasion by
means of words.

14. Uses of Insect Pheromones
In pest and Insect control management; Pheromones of
certain pest insect species, such as the Japanese beetle, acrobat
ant, and the gypsy moth, can be used to trap the respective insect
for monitoring purposes, to control the population by creating
confusion, to disrupt mating, and to prevent further egg laying.
Avoidance of inbreeding; Mice can distinguish close relatives
from more distantly related individuals on the basis of scent
signals, which enables them to avoid mating with close relatives
and minimizes deleterious inbreeding.

15. Humans; While humans are highly dependent upon visual cues,
when in close proximity smells also play a role in sociosexual
behaviors. Experiments have focused on three classes of putative
human pheromones: axillary steroids, vaginal aliphatic acids, and
stimulators of the vomeronasal organ.
Axillary steroids; Several axillary steroids have been described
as potential human pheromones:
androstadienol, androstadienone, androstenol, androstenone,
and androsterone.

16. Synthesis of Insect Pheromones
GRANDISOL
Grandisol is a pheromone primarily important as the sex
attractant of the cotton boll weevil (Anthonomus grandis), from
which it gets its name.
It is also a pheromone for other related insects.
The cotton boll weevil is an agricultural pest that can cause
significant economic damage if not controlled.
Grandisol is the major constituent of the mixture known
as grandlure, which is used to protect cotton crops from the boll
weevil.

17. Grandisol with the molecular formula C10H18O.
It is a monoterpene containing a cyclobutane ring,
an alcohol group, an alkene group and two chiral centers.
Grandisol was first isolated, identified, and synthesized by J.
Tumlinson et al. at Mississippi State University in 1969.

18. Synthesis of Grandisol
Method-I

19. Method-II
Tetrahedron 63 (23), 4 June 2007, Pages 4968-4974

20. J Org Chem. 2010 Jan 1;75(1):226-8. doi: 10.1021/jo9020375.
Method-III

21. (+)-FARANAL
[3S,4R,6E,10Z,(+)]-3,4,7,11-Tetramethyl-6,10-tridecadienal
The True Trail Pheromone of Pharaoh's Ant

22. Method-I

23. Method-II

24. BREVICOMIN
Pheromone from Dendroitis brevicomis

25. Method-I

26. J. Braz. Chem. Soc. 13 (2) • 2002
Method-II

27. Method-III

28. (+)- DISPARLURE
The gypsy moth (Porthytria dispar) is a serious pest of the
forests.
In 1976 B.A. Bierl et.al., (Science, 170,88 (1970)) isolated the
sex pheromone (+)- Disparlure from extracts of 78,000 tips of the
last two abdominal segments of female moths.

29. Chem. Ber., 109, 3375 (1976)
Method-I

30. Angew. Chem., Int. Ed., 11, 60 (1972). Klunenberg
et.al.,
Method-II

31. J. Am. Chem. Soc., 96, 7842 (1974)
Method-III

32. Mori et.al.,Tetrahedron, 53, 833 (1979)
Method-IV

33. Kossier B. E.. et.al., (J. Am. Chem. Soc., 103, 464
(1981)
Method-V

34. 3,11-Dimethy1-nonacosanone
Pheromone of German cockroaches.
Tetrahedron, Volume 72, Issue 30, 28 July 2016, Pages 4593-

35. BOMBYKOL
Bombykol or 10(E),12(Z)-Hexadecadienol.
Has been identified as a sex pheromone of the
silkworm Bombyx mori.
Discovered by Adolf Butenandt in 1959.
It was the first pheromone to be characterized chemically.
Can be used in pest control.
It has been synthesized on a gram scale.

36. Dasardhi, P., P. Neelakantan, S.J. Rao, and U.T. Bhalerao. 1991. The oxidation of
bombykol to bombykal. Synth. Comm. 21:183.
Method-I

37. Starting from vernolic acid (1), first the epoxy group was ring-
opened, resulting in a diol product (2). This diol could be
selectively cleaved to the aldehyde (3) without affecting the
carbon-carbon double bond and leaving hexenal (4) as a side-
product, that in itself may find useful applications in the flavor
industry. Protecting the carboxylic acid group and isomerization
of the double bond yielded a reactive intermediary product [12-
oxo-10(E)-dodecenoic acid (5)] which contained a carboxylic
ester and also an aldehyde functionality in conjugation with the
carbon-carbon double bond. Subsequent Wittig olefination of (5)
leads to the 10(E), 12(Z)-product (6), which is selectively
reduced to bombykol (7).

38. PLOS ONE, 2012, 7(9): e44190.
Method-II
Method-III

39. MULTISTRIATIN
Multistriatin is a pheromone of the elm bark beetle.
It is a volatile compound released by a virgin female beetle
when she has found a good source of food, such as an elm tree.
Males beetles, which carry the fungus which causes Dutch elm
disease, are attracted to the pheromone.
Hence multistriatin could be used to trap beetles and so prevent
the spread of the disease.
Note: Only the natural stereoisomer, α-multistriatin, attracts the elm bark
beetles.

40. Method-I

41. Method-II
Method-III

42. USE OF PHEROMONES IN INSECT PEST MANAGEMENT
Currently, pheromones and other semio-chemicals are being
used to monitor and control pests in millions of hectares of land.
Highly relevant for IPM programmes of tephritid fruit flies is the
use of parapheromones.
These are chemical compounds of anthropogenic origin, not
known to exist in nature but are structurally related to natural
pheromone components, that in some way affect physiologically
or behaviorally the insect pheromone communication system,
eliciting a similar response to that of a true pheromone.

43. Commercial Pheromones
Stored Product Moth „
 Warehouse Beetle „
Cigarette Beetle „
Drugstore Beetle
Red and Confused Flour Beetles „
Lesser Grain Bore

44. Uses of Pheromones
Detection „
Monitoring „
Mass Trapping „
Mating Disruption
Attracticide „
or Attract-and-Kill
Pathogen Dispersion

45. Monitoring
Monitoring is an effective way to determine the population
trends of insects and plays a critical role in pest management
programmes.
Pheromone-based behavioral manipulation has been developed
as a monitoring tool for many pests.
It involves the use of a synthetically-derived pheromone
formulated into a dispenser and trap to selectively attract and
intercept the target insect.
The advantages of using pheromones for monitoring pests
include lower costs, specificity, ease of use, and high sensitivity.

46. Mating Disruption
During mate location, sex pheromones are commonly used as
long-range cues to orient insect species toward potential mates.
Synthetic blends of sex pheromones can be used to permeate
the environment and disrupt the orientation of males to females,
thereby inhibiting the mating process.
Mating disruption in moths works mainly through competitive
attraction compared to the non-competitive mechanisms
(camouflage, desensitization, and sensory imbalance).

47. Mass Trapping
This strategy involves the use of attractive semiochemicals
(synthetic aggregation and sex pheromones, host volatiles, etc.)
involved in the mate finding and/or foraging behaviors of the target
pest with the purpose of bringing them to killing devices.
Insects are removed from the population using small amounts of
insecticides, adhesives, water, or other physical structures.
Competitiveness of traps with wild calling females, pest density,
biology and ecology of the target pest, operational costs, and
mated female immigration risk are the important considerations in
devising a mass trapping pest management programme.

48. Attract-and-Kill
The attract-and-kill method is one type of behavioral
manipulation method that combines a long-distance olfactory
stimulus to attract a particular pest in combination with some type
of killing agent.
This approach is similar to mass trapping but does not require
the physical entrapment of the target pests.
Both mass trapping and attract-and-kill approaches work best
when pest density is relatively low.

49. Pheromone Lures
Fiber „
Plastic Tube „
Rubber Septa „
Controlled Release Membrane „
Beads „
 Oil Solutions „
Gels

50. Trap Types
Funnel Traps „
Grain Probe Traps „
Pitfall Traps „
Sticky Traps „
Box Traps „
Wing Traps „
Delta Traps „
Diamond Traps „
Discreet Trap

51. Additional Attractants
Food odors enhance the response to pheromones for some
insects. „
Flower odors increase response to pheromones in some
insects. „
These attractants may need to be added to trap for it to be
effective.
Pheromone Trapping Principles
Active Space „
Additional Attractants „
Temperature Effects
Trap Placement
 Trap Density