Parasitoids are insects that live on or in the body of another insect host, from which they obtain food and protection for at least part of their lifecycle. They are classified based on their developmental site in the host (ecto- vs endoparasitoid), competition among immature stages (simple, multiple, super parasitism), number developing from a single host (solitary vs gregarious), host specificity (monophagous, oligophagous, polyphagous), and trophic level (primary, secondary, tertiary parasitoids). Important agricultural parasitoids include Trichogramma spp., Chelonus blackburni, Bracon brevicornis, and

1. Parasitoids
M..Sermaraja
J.Adlin Prajula
V.Adhithyan
S.Anitha
A.K.Bharath Kumar

2. Parasitoids
• Parasitoid is an insect living on or in the host body of another insect, called
host from it gets protection and food at least during one stage of its life
history.
• An insect parasite of an arthropod
• Parasitic only in its immature stages
• Destroying its host in the process of its development
• Free living as an adult

3. Characteristics of parasitoids
• A parasitoid is generally smaller than its host or some times larger .
• Posses distinctive sense organs and ovipositor.
• Obtain its nourishment and shelter from its host during a part of its life.
• Highly host specific.
• More than one parasitoid may attack a single host unlike in predator.
• The host is not killed immediately, but continue to live for a long or short
period.

4. History
• 1602 – Aldrovandi noted cocoons of Apanteles glomeratus on parasitized
Pieris rapae.
• 1701 – Leeuwenhoek ,honor of being first to understand parasitism.
• 1800's - Darwin discussed "Ichneumonids" as natural control factors for
cabbage caterpillars.
• 1827 - Hartig (Germany) suggested the mass rearing and release.
• 1882-Trichogramma sp. were shipped from the U.S. to Canada.
• 1913 - O.M.Reuter coined the term parasitism.
• 1926 surveys in the Konkan coast - Goniozus (=Parasieorola) nephantidis
and Trichospilus pupivora.
• 1930 - Indigenous Trichogramma minutum employed against the early
shoot borer of sugarcane in Mysore.
• 2004 - E. guadeloupae La Réunion, an island in the south‐west Indian
Ocean
• 2010 – Acerophagus papayae for control of Papaya mealybug.

5. Based on the developmental site in the host
Ectoparasitoid
• Bracon brevicornis on Coconut
black headed caterpillars.
Endoparasitoid
• Eriborius trochanteratus on
Coconut black headed caterpillar.

6. Based on competition among immature stages of
parasitoid
Simple parasitism.
• Interspecific competition
• Host parasitized by one or more
genus/species
• Death one of the individuals occurs
• Eg:Apanteles yakutatensis
(Braconidae) and Madremyia
saundersonii(Tachinidae) on
Autographa californica
Multiple parasitism
• Single attack by parasitoid
irrespective of number of eggs laid.
• Goniozus nephantidis on BHC
Super parasitism
• Intraspecific competition
• Host attacked more than once by
single species of parasitoid.
• Trichogramma evanescnes

7. Based on number of parasitoids developing from a
single host.
Solitary parasitoid
• Chelonus blackburni on Potato
tuber moth.
Gregarious parasitoid
• Copidosoma koehleri on Potato
tuber moth

8. Based on host specificity
Monophagous Oligophagous Polyphagous
• Parasierola(Goniozus)
nephantidis on Coconut
Black Headed caterpillar.
• Attacking a group of
related host species.
• Braconidae and
Ichneumonidae.
• Trichogramma sp. on eggs
of many Lepidopteran
species.

9. Based on the tropic levels
• Primary parasitoids: Parasitoid attacking a pest - (eg) Trichogramma sp.
• Secondary parasitoids: Parasitises a parasiotoid - (eg) Opisina
arenosella (pest) - Bracon brevicornis (Primary parasitoid) – Pleurotropis
sp. (secondary parasitoid) – Harmful interaction
• Exception- Nesolynx thymus hyperparasitoid of Uzi fly- Beneficial.
• Tertiary parasitoids: Parasitoid attacking a secondary parasitoid
(eg) Trichospilus coerulescens.
• Hyperparasitoids.

10. Hyperparasitoid Chalcid wasps emerging from Bracon spp. cocoons.

11. Trichogramma evanescens wasp parasitizing Pieris rapae egg
Egg parasitoids
Trichogrammatidae and Scelonidae

12. Bracon sp. on Manduca sexta
Larval parasitoids
Braconidae,Bethylidae,Ichneumonidae,Platygasteridae

13. Lraval parasitoid - Endoparasite

14. Diadromus collaris wasp on a pupa of diamondback
moth
Pupal parasitoids
Chalcididae,Eulophidae

15. Pyrilla nymph carrying the larvae of E. melanoleuca
Nymphal parasitoid
Aphelinidae,Epipyrophidae

16. • Egg – larval parasitoids: Chelonus blackburni and Copidosoma koehleri
on Potato Tuber Moth.
• Larval - pupal parasitoids : Carcelio illota on Helicovera armigera
• Adult parasitoids : Blaesoxipha kellyi a parasitoid of locust.

17. Parasitoids of agricultural importance
• Trichogramma sp. – egg parasitoid of sugarcane intermode borer.
• Chelonus balckburni – egg larval parasitoid of potato tuber moth
• Bracon brevicornis – Larva parasitoid of coconut blackheaded
caterpillar (BHC)
• Parasierola nephantidis – Larva parasitoid of coconut BHC
• Eriborus trochanteratus – Larva parasitoid of coconut BHC
• Eucelatoria bryani – Larval parasitoid of American
bolloworm Helicoverpa armigera
• Sturmiopsis inferens – Larval parasitoid of sugarcane shoot borer
• Eucarcelia illota – Larval pupal parasitoid of H. armigera
• Trichospilus pupivora – Pupal parasitoid of coconut BHC
• Tetrastichus israeli – Pupal parasitoid of coconut BHC

18. Hymenopteran parasitoids
• Important and economically effective parasitoids
• Small to medium sized insects
• Posses sharp ovipositor
• Families: Ichneumonidae, Braconidae, Chalcididae, Encyrtidae,
Eulophidae, Trichogrammatidae, Platygasteridae, Scelionidae, Bethylidae.

19. Ichneumonidae
• Brilliantly marked active insects with long ovipositor
• Parasitic on Lepidoptera,Coleoptera and Diptera
• Adults active on sunny weather attracted by umbelliferous flowers
• Gambroides javensis on Scirpophaga excerptalis

20. Braconidae
• Endoparasites.
• Preferred host – Lepidopterous larvae.
• Pupation takes place inside a cocoon.
• Cotesia flavipes and Bracon brevicornis on Opisina arenosella.
• Bracon gelechidiphagus on Scrobipalpa blapsigona.
Bracon brevicornis Cotesia flavipes

21. Trichogrammatidae
• Egg parasitoids.
• Broad range of parasitism.
• Trichogramma australicum can parasitise around 150 host species.
Trichogramma platneri
ovipositing on egg of Trichoplusia ni

22. Eulophidae
• Ectoparasitoids
• Host: Lepidoptera.
• Attacks egg and pupal stages.
• Trichospilus pupivora on pupae of black headed caterpillar(BHC)
• Tetrastichus spp. on eggs of paddy stem borer.
Trichospilus pupivora Tetrastichus spp.

23. Encyrtidae
• Ectoparasitoids
• Host : Hemiptera,Lepidoptera.
• Ooencyrtus pyrillae - egg - Pyrilla perpusilla.
• Copidosoma koehleri – egg larval – Phthorimaea operculella.
• Acerophagus papayae, Anagyrus loecki, Pseudoleptomastrix mexicana –
Nymphal and adult – Paracoccus marginatus.
Acerophagus papayae

24. Platygasteridae
• Parasitoids of Cecidomyiidae
• Platygaster oryzae on rice gall fly Orseolia oryzae.
Platygaster oryzae

25. Scelionidae
• Very small egg parasitoids.
• Telenomus beneficians and Telenomus rowani on Scirpophaga incertulas
• Telenomus remus on Spodoptera litura
• Telenomus alecto on Scirophaga sp,Chilo sp.
Telenomus remus on
Spodoptera eggs
Telenomus rowani

26. Chalcididae
• Primary or secondary parasitoids.
• Lepidopterous larvae or pupae.
• Brachymeria nephantidis-pupal- Opisina arenosella

27. Bethylidae
• Parasitoids of leidopteran caterpillars
• Goniozus nephantidis on Opisina arenosella.

28. Aphelinidae
• Aphelinus mali – Parasitoid of Apple wolly aphid
• Encarsia guadaloupae – Parasitoid of invasive Rugose spiralling whitefly.

29. Dipteran parasitoid
Tachinidae
• Eggs –one to many laid ,glued to the body wall of the host.
• In some cases laid on foliage to be ingested by host.
• Maggots- sometimes deposited on the bodywall of the host.
• Feed on muscles and fat bodies
• Pupation
• Adults resemble houseflies
• large in size
• more bristly
• Found resting on foliage and flowers

30. • Endoparasitoids on larvae
• Sturmiopsis inferens infesting early shoot borer
• Spoggoisa bezziana on Black headed caterpillar
• Euceletoria bryani on Helicoverpa armigera
Sturmiopsis inferens Euceletoria bryani

31. Lepidopteran parasitoid
• Epiricrania melanoleuca (Epipyropidae)
• Parasitises nymphal stage of Pyrilla spp.
• Recognised by the presence of fleshy, ellipsoidal larvae with white waxy
cover carried on the body of the nymphs.
• Presence of parasitic larvae on the body of the leafhopper is always
indicated by the elevated position of the wing on one side.

32. • Boat-shaped white cocoons can be observed on leaves with hopper
infestation.
• Adult moths of both sexes are small, dark brown, triangular in outline,
with prominent bipectinate antennae .

35. Mass production of Chelonus blackburnii
• Take 100 fresh corcyra eggs of 0-24 hr old which are not exposed to UV
and paste to 5 x 5 cm card.
• This card containing eggs is exposed to 30 adults of C. blackburnii adults
in a 1.5 L container for parasitization.
• The plastic container has windows with plastic mesh for aeration.
• Two cotton swabs, one soaked in 10% honey solution and the other in
drinking water
• The egg card after exposing to C. blackburnii for 24 hr is removed and
placed on 500 g sterilized cumbu medium.
• In 30 days time, adults start emerging from the cocoons formed in the
cumbu (pearl millet) medium after completing development
on Corcyra larvae.
• The adults live for 25 days and their fecundity is about 400 eggs.

36. Potato tuber moth-Host
• A set of 1500 eggs are laid on a cloth are stapled to a card.
• The plastic container (14 cm x 11 cm) with parasitised eggs is fixed with plastic
mesh for aeration.
• Two cotton swabs, one soaked in 50% honey solution and the other in drinking
water
• The PTM egg card after exposing to C. blackburnii for 24 hr is removed and
placed on punctured potatoes.
• The bottom of this container is lined with sterilized sand.
• In 25-27 days time, adults start emerging from the cocoons formed in sand
at the bottom of the cage or sometimes inside potatoes after completing
development on potatoes.
• The adults live for 23-31 days and their fecundity is about 288-390.
• Parasitoid host ratio of 1:50 should be maintained and the fresh lot of eggs
provided every day.

38. Epiricrania melanoleuca (Epipyropidae;Lepidoptera)
• The initial culture of Epiricania melanoleuca is started by collecting the
cocoons of the parasitoid from the field.
• The cocoons are kept in 5 cm petridishes the bottom of which is lined by filter
paper.
• The moths emerge in 5-7 days and mate immediately.
• The females readily lay eggs on the filter paper provided.
• The larvae from these eggs hatch within a week.
• 5 day old 100 nymphs / adults of pyrilla and 200-400 freshly emerged larvae of
the parasitoid are kept in a glass tube (15 x 5 cm) for 15-30 minutes

39. • For further rearing the parasitized individuals are transferred in battery jars where
sugarcane leaves and diet containing 2.5 percent sugar and 2.5 protinules is made
available.
• The optimum room temperature for rearing the parasitoid is 27-30 degree C.
• Nylon net field cages 3x2x2 m. can also be used for mass multiplication of E.
melanoleuca.
• Sugarcane or sweet sorghum plants grown inside the cages are infested with laboratory
reared sugarcane pyrilla eggs.
• Once the pyrilla are 5 days old, the newly emerged E. melanoleuca are introduced into
of such cages.
• The cocoons of E. melanoleuca are collected after about a week by cutting the leaflets
which could then be released in the fields.
• Efforts are on to multiply E. melanoleuca on semisynthetic diet so that the labour on
host rearing could be saved.

40. Sturmiopsis inferens (Tachinidae,Diptera)
• The females of Sturmiopsis inferens are easily identified by the presence of
conspicuous whitish band on the vertex and the two long downwardly directed
fronto-orbital bristles on either side
• The males and females are separated and released in two separate cages.
• For mating freshly emerged females are paired with 2 day old males in 8x2 cm
glass vials which are gently agitated in bright sunlight or under artificial light.
• Mating commences within 20 seconds.
• The mated females are collected daily and kept in small gestation cages (12 cm
x 12 cm x 7 cm) and are provided with cotton swabs soaked in water and sugar
solution and sugar cubes/split raisins.
• The adult food is changed every day.

41. • A male can effectively inseminate 4-5 females for a period of 4 days after
which it is discarded (in the field).
• The female, after a gestation period of 8 days is pinned ventrally through
the thorax and dissected in 2% sodium chloride by using another pin.
• The abdomen is split open along the ventral suture removing the uterus in
the process.
• The maggots are freed from the ovary using two pins which forces most of
the active maggots to emerge from the chorion.
• The maggots are washed in sterile distilled water.
• The active larvae are inoculated with 2 maggots by holding healthy full
grown larvae between the fingers.

42. • The larvae with maggots are reared on artificial diet.
• The inoculation of maggots is also accomplished by suspending the
maggots in 0.15% agar solution and spreading it uniformly in a large
petridish @ 2 parasitoid maggots for one Sesamia larva.
• The petridish is closed and covered with black cloth. Within 15 minutes the
maggots enter the body of the larva and then the inoculated larvae are
transferred to artificial diet.
• The puparia, collected between 6th and 22nd day are disinfected with ethyl
alcohol and washed thrice before keeping them over blotting paper/filter
paper.
• These are placed in adult emergence cage (34 x 23 x 27 cm) where high
humidity (70-90%) is maintained.
• Two thirds of the total fly production is released and the remaining utilized
for continuing the culture.

43. Goniozus nephantidis(Bethylidae,Hymenoptera)
• The parasitoid is multiplied on Corcyra cephalonica larvae in diffused light.
• A pair of parasitoid is introduced in tube (7.5 x 2.5 cm).
• The adults are provided honey in the form of small droplets on wax coated
paper.
• After a pre-oviposition period of six days one healthy last instar larva is
provided in a vial.
• The larvae parasitised i.e., containing eggs of G.nephantidis are removed
regularly from the vials till the death of the female.
• Such larvae are kept in accordion type strips of paper in plastic boxes
which are covered by muslin cloth.
• Considering the fecundity as 20-50, the female is capable of parasitising 6-
7 larvae in three oviposition spells each separated by 4-5 days.
• The life cycle of the parasitoid is completed in 10-14 days (incubation 24 -
36 hrs, larval feeding 36-48 hrs, prepupal stage 48-60 hrs and cocoon
period 48 to 56 hrs + resting adult inside the cocoon 108-128 hrs).

44. Mass production of Acerophagus papayae
• Sprouted potatoes(7 days old) planted in sterile river sand is used for the
rearing the papaya mealybug.
• Treated with fungicide solution to prevent infection by pathogen.
• The mealybugs are collected from the field and dusted over the sprouted
potatoes.
• The setup is placed in rearing cage covered with a black cloth.
• Adults of Acerohagus papayae are released into the cage and parasitisation
takes place.
• The adult parasitoids are collected from the cage and released in the field.
• 100 adults are released to control papya mealybug in an area of 12 acres.

45. Sprouted potatoes
Mealybugs relaesed over
thre sprouts
Mealybugs infested
potato sprouts
Field release
Parasiotids released
in the cage

46. Field release procedure- Bracon spp,
Stapling Bracon card with pupae Releasing adults in tub method
 4000-5000 pupae cocoons ha-1 or 2000-5000 adults ha-1 will effectively control
the pests. Depending upon the need weekly releases need to be made.

47. Procedure for Tricho card usage
• Tricho cards should be packed in such a way that the parasitised surface is
on the inner side.
• Emergence date should be specified on cards for the guidance of the users.
• Tricho cards should be stapled on the inner-side of the leaf to avoid direct
sunlight.
• Card should be stapled in morning hours and just before emergence to
avoid predation.
• Farmers should refrain from using pesticides in the field
where Trichogramma are released.
• If need arises selective / safer pesticides can be used and it is to be ensured
that pesticides are used 15 days before or after release of Trichogramma.

48. Field release – Dosage.
• Chelonus blackburnii
• Potato tuber moth: Two releases @50,000 adults release-1 in the field and 5
adults kg-1 potatoes in godowns
• Cotton bollworms: 50,000 adults week-1, first release coinciding with
sighting of eggs in the field.
• Helicoverpa armigera : at weekly intervals, first release coinciding with
sighting of eggs in the field.
• Platygaster oryzae - 1/10 square meter for the control of Rice gall midge.
• Sturmiopsis inferens @ 312 gravid females /ha for the control of Early
shoot borer in sugarcane.
• Trichogramma chilonis - 4th and 11th week @ 1,25,000/ha for the control
of Sugarcane internode borer.
• Epiricrania melanoleuca - 4-5 lakh | 4000-5000 viable cocoons /ha for the
control of Pyrilla purpusiella.

49. Advantages
• Pest management with parasitoids costs nothing
• At low pest densities, parasitoids can suppress infestations to below
economic thresholds
• Parasitoids reduce the number of pests surviving to the next
generation
• They are compatible with other biological control agents (diseases
and predators)
• Parasitoids are host specific
• Some parasitoids affect feeding behaviour e.g. parasitised larvae eat
less than healthy ones
• Parasitoids are efficient host searchers – they can find hosts even
when pest densities are low

50. Limitations
• They are often (but not always) host-specific and often will attack only one
species of pest.
• They are generally more delicate than predators and hence more vulnerable
to pesticides.
• Because parasitoids spend most of their life cycle developing within their
prey, they are less visible than predators, and their performance may be
underestimated as a result.
• Hyperparasitism.
• Labour intensive.
• Lack of artificial diet- need for cultivation of host plants.
• Mass culture procedures have not been standardised for all available
parasitods.

51. Current areas of research
• What’s gotten into you?: a review of recent research on parasitoid
manipulation of host behavior Kelly L Weinersmith.
• Parasitised trichocards after 4 days of parasitisation can effectively stored
up to 15 days without much effect on adult emergence.(Effect of low
temperature storage of trichocards parasitised by Trichogramma chilonis
Ishii and Trichogramma japonicum Ashmead ; M. BHARGAVI AND K.V.
NAIK).
• A minimum of 60% emergence rate and 3 days of longevity, 1 month of
storage duration can be recommended for T. chilonis lab, T. japonicum, and
T. achaeae at 10 °C. (Short-term storage of the egg parasitoids,
Trichogramma and Trichogrammatoidea Enakshi Ghosh* and Chandish R.
Ballal)
• Vacuum packing enhanced storability of C. cephalonica eggs by 3- to 4-
fold as compared to the traditional method of storage.(Vacuum packaging
of Corcyra cephalonica (Stainton) eggs to enhance shelf life for
parasitization by the egg parasitoid Trichogramma chilonis Sushil K. Jalali
*, T. Venkatesan, K. Srinivasa Murthy, Rajaratnam J. Rabindra, Y. Lalitha)