info-chemiclas inhance the efficacy of natural enemies in biological control. Infochemicals are chemicals that convey information in an interaction between two individuals evoking in receiver a behavioural or physiological response that is adaptive to one of interactants or both.

1. 1

2. 2

3. 3

4. INFOCHEMICALS
 Infochemicals are chemicals that convey
information in an interaction between two
individuals evoking in receiver a behavioural or
physiological response that is adaptive to one of
interactants or both.
Nina E. Fatouros et.al.
4

5. Classification of infochemicals
Dicke and sabelis(1988)
5

6. Pheromones
Monitoring
Maas
trapping
Mating
disruption
6

7. Allelochemicals
Allelochemicals mediate interactions of
individuals belonging to different species.
Allomones
Kairomones
synomones
7

8. Allomones
Plant based :-
Direct effect-herbivores
Indirect effect-natural enemies
Insect based:-
Ex.Romalea guttata(grasshopper)
8

9. Kairomones
A kairomone is an allelochemical that
evokes in the receiver a response i.e.
adaptively favourable only to the
receiver, not the emitter.
(Dicke and Sabelis, 1988).
9

10. Kairomones
 Adult and larval parasitoids kairomones of their
target stage or byproduct
of their host.
 Pupal parasitoids kairomones from the preceding host
stage
 egg parasitoids eggs ,other non-target host stages,
especially adults and adult-related by-
products
10

11. Conti…
Plant based:-
Plant produced chemicals
Body odours of herbivores
Natural enemies
Ex.Tricosane
Eggs of Heliothis zea
Trichogramma evanescens
Lewis et al.,1972 11

12. Conti…
Insect based:-
Chemicals emitted from different stages of host
(eggs, larvae, pupae, adult), host by-products
(e.g., frass, exuviae, mandibular gland secretions,
defense secretions etc.)or intra-specific infochemicals
(pheromones)
Fecal volatiles of both larvae and adults of the elm leaf beetle
(Xanthogaleruka luteola) were attractive to its egg parasitoid
Oomyzus gallerucae (Meiners and Hilker 1997).
12

13. Conti…
 A synthetic component of the sex pheromone of Euproctis taiwana
(Shiraki) (Lepidoptera: Lymantriidae),i.e. (Z)-16-methyl-9-
heptadecenyl isobutyrate, attracted both the wasp,Telenomous
euproctidis, and male E. Taiwana.
Norio Arakaki et.al.1996
13

14. Aggregation pheromones as kairomones:-
Gryon pennsylvanicum males of the leaf-footed plant
bug (Leptoglossus australis)
Telenomus calvus utilize the aggregation pheromone of the male
bugs,(Podisus maculiventris) i.e.terpineol, to come in the host
male's vicinity
14

15. Continued…….
Insect pheromones as kairomones:-
The use of volatile host pheromones by egg parasitoids was shown
for the first time by Lewis et al. (1982)
Volatiles of the abdominal tips of female Heliothis zea moths as well
as synthetic sex pheromone of H. zea females (hexadecanal, (Z)-7-
hexadecenal, (Z)-9-hexadecenal, and (Z)-11-hexadecenal) increased
parasitization rates by Trichogramma pretiosum.
kairomones
15

16. 0
2
4
6
8
10
12
14
16
1 2 3 4 5
H.armige
ra scales
C.cephal
onica
scales
control
Kairomones of Heliothis armigera and Corcyra
cephalonica and their influence on parasitic potential
of Trichogramma chilonis
Parasitoid age(days
Eggsattacked
16

17. Compounds identified from H.armigera and
C.cephalonica moth scales
T.N.Ananthakrishnan et. al. 1991
17

18. Kairomones play a very important in
host recognition
 Strand and Vinson (1982) showed in an elegant series of
experiments how, if glass beads the size of host eggs are uniformly
coated with material present in accessory glands of the female host ,
and are presented to females of Telenomus heliothidis (Scelionodae)
 The insect will readily attempt to drill the beads with their ovipositor
 when presented with either clean glass beads or host eggs that had
been washed in certain chemicals, were ,on the whole, unresponsive.
 Van Alphen and Vet (1986) showed that the braconid parasitoid
Asobara tabida discriminates between the kairiomone produced by
Drosophila melanogaster and that by D. Subobsucura.
18

19. The effect of aphid-extract on the behaviour
of Coccinella septempanctata
8.30%
18.40%
25.80%
40.80%
6.70%
AC1
AC2
AC3
AC4
control
The percentage of number of C. septempunctata adult directed or attracted to the different
concentration of Aphid extract (AC) in addition to control.
MOURAD L. SHONOUDA,1999 19

20. The mean path length(cm) and the mean turning rate (turns/min)
exhibited by C.septempunctata under the effect of different
concentration of aphid-Extract(Ac)
MOURAD L. SHONOUDA,1999
20

21. The mean of time arrested by C.septempunctata adults inside the half
Petri-dish treated with aphid extract (AC) or distilled water (Control)
MOURAD L. SHONOUDA,1999
21

22. Kairomonal effect of different combinations of
synthetic kairomones on the egg parasitoids
Trichogramma exiguum and T. japonicum
3 synthetic kairomones viz.
Docosane(D),Tricosane(T) and pentacosane(P) in 3
concentrations(10ppm(1),20ppm(2),30ppm(3))
Trichogramma exiguum -% parasitization max with
Combination P3+D2+T3
T. japonicum - % parasitization max with
Combination P2+D3+T2
Babita yadav et.al,2008
22

23. Egg parasitoids exploiting chemical
information
CLOSE RANGE/LONG RANGE AND CONTACT
INFOCHEMICALS:-
Host cues;-
 Laing (1937) first to report arrestment of T. evanescens wasps
by chemical traces left by the grain moth Sitotroga cerealella.
 Lewis et al. (1971,1972) found that wing scales left by
ovipositing H. zea or Plodia interpunctella moths were used as
kairomones by T. evanescens.
23

24.  Several follow-up studies showed a response of egg
(larval) parasitoids to residues of the adult host, such as
wing scales of butterflies or moths.
 Jones et al. (1973) found hydrocarbons like tricosane in
wing scales of H. zea as biologically active cues,
eliciting significant orientation and stimulation of
parasitism by T. evanescens.
 Colazza et al. (2007) revealed that n-nonadecane, a
cuticular hydrocarbon released by the tarsi and scutella
of female N. viridula bugs had a kairomonal activity on
the egg parasitoid Tr. basalis acting as a "host gender
recognition" cue for the egg parasitoids.
Continued…….
24

25. Response to plant cues
Egg parasitoids Host Source Response
Scelionidae
Trissolcus basalis Nezara viridula Bean: infested with host adults and
3- to 4-d-old eggs
Attraction
Eulophidae
Chrysonotomyia ruforum
Oomyzus gallerucae
Diprion pini
Xanthogaleruca
luteola
Pine: infested with 3-d-old host
Elm: infested with 3-h to 5-d-old
host egg masses
Arrestment
Arrestment
Trichogrammatidae
Trichogramma chilonis
Trichogramma brassicae
(or Trichogramma maidis)
Trichogramma pretiosum
Helicoverpa
armigera
Plutella xylostella
Pieris brassicae
Ostrinia nubilalis
Spodoptera
frugiperda
Heliothis zea
Sorghum and pigeon pea:
uninfested plants
Cabbage: synthetic green leaf
volatiles
Brussels sprouts: leaves infested
with 3-d-old egg clutches
Maize: extracts in combination with
the synthetic host pheromone and
host eggs
Cotton: leaves infested with host
caterpillars
Tomato: plant extracts
Arrestment
Attraction
Arrestment
Arrestment
Attraction
Increased parasitism
Myrmaridae
Anagrus nilaparvatae Nilaparvata lugens Rice: host damaged plants Attraction 25

26.  Long range infochemicals:
 Plant cues-
 Salt (1935) stated that most parasitoids are first attracted to
a certain typeof environment and then to a particular host .
 Vinson (1981)lists factors involved in habitat location such as
sound, visual cues, forms of electromagnetic radiation, and
volatile chemicals.
 the eulophid egg parasitoid, Chrysonotomyia ruforum, is
attracted by volatiles of Scots pine (Pinus sylvestris)
induced by eggs of the sawfly Diprion pini (Hilker et al.
2002; Mumm and Hilker 2005).
26

27. 27

28. Response to volatile kairomones of adult hosts
Egg parasitoid Host Source Response
Scelionidae
Trissolcus simoni
Trissolcus basalis
Telenomus remus
Telenomus euproctidis
Telenomus isis
Eurydema ventrale
Nezara viridula
N. Viridula
Spodoptera frugiperda
Euproctidis taiwana
Sesamia calamistis
Males and females
Mated females in a
"preovipositional state“
Virgin males
Defensive metathoracic
gland scent
Virgin female abdominal
tips
Synthetic sex pheromone
Virgin females
Calling virgin females
Attraction
Attraction
Attraction
Increased parasitism rates
Attraction in the field
Phoresy
Arrestment
Eulophidae
Chrysonotomyia ruforum Diprion pini
Neodiprion sertifer
Synthetic sex pheromone Arrestment
Encyrtidae
Ooencyrtus nezarae Riptortus clavatus Synthetic aggregation
pheromone of male bugs
Attraction in the field
28

29. Trichogrammatidae
Trichogramma evanescens
Trichogramma brassicae (or
Trichogramma maidis)
Trichogramma pretiosum
Trichogramma evanescens
later Trichogramma maidis
(=Trichogramma brassicae)
Trichogramma chilonis
Ephestia spp.
Plodia interpunctella
Pectinophora gossypiella
Spodoptera littoralis
Earias insulana
Pieris brassicae
Ostrinia nubilalis
Heliothis/Helicoverpa zea
Plutella xylostella
Mamestra brassicae
P. Brassicae
Helicoverpa assulta
Plutella xylostella
Synthetic sex pheromone
Synthetic components of sex
pheromone
Mated female butterflies
Synthetic antisex pheromone
Calling virgin females
No response to main sex
pheromone component
Eggs + pheromonal blend +
maize extract
Abdominal tips
Excretion and synthetic sex
pheromone of virgin females
Calling virgin females
Synthetic compound of sex
pheromone
Calling virgin females
Host sex pheromone odor
No response to main sex
pheromone component
Virgin females in "mate-
acceptance posture," no sex
pheromone known
Sex pheromone of virgin
moths
Main component of sex
pheromone
Synthetic sex pheromone
blend
Arrestment
Attraction
Arrestment
Phoresy
Attraction
Increased parasitism
Arrestment
Arrestment
Increased parasitism
Arrestment
Arrestment
Arrestment
Arrestment
Attraction
29

30. Responses to adult host residues
Egg parasitoid Host Source Response
Scelionidae
Trissolcus basalis
Telenomus isis
N. Viridula
Sesamia calamistis
Chemical traces of virgin
males and mated females in a
"preovipositional state“
n-nonadecane, cuticular
hydrocarbon of female hosts
Chemical traces by virgin and
mated females
Arrestment
Arrestment
Eulophidae
Oomyzus galerucivorus Galeruca tanaceti Adult feces on substrate Arrestment
Trichogrammatidae
Trichogramma evanescens
(later Trichogramma maidis
now Trichogramma brassicae)
Trichogramma evanescens
Trichogramma chilonis
Pieris brassicae
Pieris rapae
Mamestra brassicae
Heliothis zea
Plodia interpunctella
Sitotroga cerealella
Corcyra cephalonica
Cabbage leaves treated with
wing scales from adult female
hosts
Body scales and their hexane
extracts
Tricosane from scale extracts
Traces of adult hosts
Saturated hydrocarbons,
mainly tricosane
Arrestment
Arrestment and increased
parasitism
Arrestment
Increased parasitism
Braconidae
Ascogaster quadridenata Cydia pomonella Volatiles of host scales Attraction
Pteromalidae
Halticoptera rosae Rhagoletis basiola Marking pheromone of female
flies
Increased parasitism and
arrestment
30

31. Response to kairomones associated with host
eggs
Egg parasitoid Host Source Response
Scelionidae
Trissolcus brochymenae Murgantia histrionica Eggs
Egg extracts
Arrestment
Increase in encounters
Eulophidae
Ooencyrtus kuvanae Lymantria dispar Airborne chemicals of
fresh egg masses
Accessory gland secretion
Arrestment
Trichogrammatidae
Trichogramma
evanescens later
Trichogramma maidis
(=Trichogramma
brassicae)
Trichogramma ostriniae
Trichogramma brassicae
(or Trichogramma maidis)
Pieris brassicae
Ostrinia furnacalis
Pieris brassicae
Ostrinia mubilalis
Egg wash
Airborne chemicals of egg
masses
Accessory gland secretion
of mated host females
Accessory gland secretion
of mated host females
Airborne chemicals of egg
massesSurface extracts of
egg masses
Arrestment
Arrestment and attraction
Arrestment
Increased mobility and
arrestment
31

32. General patterns in egg parasitoid–foraging strategies
32

33. Kairomones from scarabaeid grubs and their frass as cues in
below-ground host location by the parasitoids Tiphia vernalis and
Tiphia pygidialis
33

34. Response of
Tiphia
vernalis and
T. pygidialis
to their
normal hosts
(Popillia
japonica and
Cyclocephal
a spp.
respectively)
and to cues
from
non-host
grubs
34

35. Response
of Tiphia
vernalis
and T.
pygidialis
to frass
from their
normal
hosts
(Popillia
japonica
and
Cycloceph
ala spp.
respective
ly) and to
frass from
non-host
grubs
35

36. Synomones
An infochemical of an
organism that on emission
evokes a behavioral or
physiological response in the
receiver, an individual of a
different species, adaptively
favorable to both receiver
and emitter.
Ex. Maize (Zea mays) plants infested by Noctuid
larvae(Spodoptera frugiperda and S. exigua ) emit terpenoids and
indole that attract a parasitic wasp, Cotesia marginiventris
36

37. Herbivore-induced plant
volatiles attract carnivorous
arthropods
 Chemical stimuli are an important source of information for
arthropods and may convey information about the presence and
quality of resources, competitors, and enemies (Carde and Bell,
1995; Roitberg and Isman, 1992).
 Predatory arthropods that forage for herbivores exploit volatiles
related to herbivores.
 These volatiles do not originate from their prey itself, but from the
prey's food plant, which produces the cues in response to herbivore
damage
 This information emitted by plants can be specific for the herbivore
that damages the plant, and thus the signal may be a reliable
indicator of herbivore presence and identity (Dicke and Vet, 1999;
Vet and Dicke, 1992).
37

38. 38

39. Metabolic pathway leading to volatile emission from herbivore damaged plants
and exemplary structure of volatile compound.
39

40. HIPVs or Synomones
monoterpenes and sesquiterpenes
green leaf volatiles Ex.- (Z)-3-hexenal,
(E)-2-hexenal, (Z)-2-hexenol, (E)-2-hexenol
and (Z)-3-hexenyl acetate.products of the
octadecanoid pathway
aromatic metabolites of the shikimate,
tryptophan and phenylalanoic ammonia
lyase pathways (e.g., indole and methyl
salicylate)
40

41. Chemicals act as plant signals
methyl jasmonate (MeJA)
cis-jasmone
methyl salicylate
hexenyl acetate
41

42. Elicitors of HIPVs
β-Glucosidase- from regurgitate of
Pieris brassicae
Volicitin(N-(17-hydroxylinolenoyl)-l-
glutamine)-from oral secretion of beet
armyworm larvae (Spodoptera exigua)
42

43. Practical uses of infochemicals
Tritrophic interactions
Push-pull strategy
43

44. Tritrophic Interaction
Plants
Herbivores
Predator/parasitoids
44

45. Trophic interaction
among host
plants, herbivore,
and predator or
parasitoids
mediated by plant
volatiles
45

46. Scheme of
terpene-mediated
interactions of a
maize seedling
above and below
ground.
46

47. 47

48. Push-pull strategy
 The term ‘push–pull’ was first coined by pyke et al
1987.
 use of repellent and attractive stimuli.
 Trap plants:-Napier grass and Sudan grass
 Repellant crop:-molasses grass and silverleaf
desmodium
 Volatiles in trap crops:-green leaf volatiles hexanal,
(E)-2-hexenal, (Z)-3-hexen-1-ol, and (Z)-3-hexen-1-yl
acetate
48

49. 49

50. 50

51. Push-Pull
Strategies
51

52. Merits and Demerits of Infochemicals
Merits:-
 Active at low concentration
 Ecofriendlly
 Non-toxic to wild life
 Demerits:-
 Development and registration requires huge investment.
 Do not provide immediate control
 Products in market are not of uniform quality
52

53. Future Thrust
Isolation,identification,bioefficacy and synthesis of kairomones as
one of the thrust area.more and more research should be done to
explore new synthetic kairomones
Two areas where future efforts might result in major breakthroughs
in HIPVs or synomones are:-
1) signal molecule recognition
2) downstream signal transduction
53

54. Conclusion
 Kairomones and Synomones play important role in
recruitment of natural enemies.
 Infochemicals are increasingly being integrated
with a range of methods producing new schemes.
 In addition to traditional approaches, research
efforts should be continued to combine and develop
new and innovative approaches including the
manipulation of natural enemy behaviour through
infochemicals.
 Armed with these tools, scientist may soon be able
better the understand the role of infochemicals and
apply this knowledge to improve biological control
of herbivore pests.
54

55. Thank you
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