This document discusses biological control as a component of integrated pest management. It defines biological control as using natural enemies like parasites, predators, or pathogens to maintain pest populations at lower levels. There are three approaches to biological control - conservation of natural enemies, classical biological control using introduced natural enemies, and augmentation of natural enemies through mass rearing and release. The document provides examples of commonly used biological control agents like predators, parasitoids, entomopathogenic fungi, viruses, bacteria, and nematodes. It describes their characteristics, modes of action, field application methods and dosages for different target pests. Biological control is highlighted as a highly economical, self-perpetuating and environmentally friendly pest management strategy.

1. Lecture no 10
BIOLOGICAL CONTROL
RK Panse
Assistant Professor
Department of Entomology
CoA, Balaghat, M.P.
Subject: Principles of Integrated pest and Disease Management

2. Definition
H. S. Smith (1919)- First used term "biological control" to signify the use of
natural enemies (whether introduced or otherwise manipulated)
to control insect pests.
B. P. DeBach (1964) -Further refined the term and distinguished "natural control"
from "biological control":
Natural control is "the maintenance of a more or less fluctuating population density
of an organism within certain definable upper and lower limits over a period of
time by the actions of abiotic and/or biotic environmental factors" .

3. Why biological control……….
 Highly economical
 Selective with no side effects
 Self propagating and self-perpetuating
 Pest resistance to BCAs is virtually unknown
 No harmful effects on humans, livestock's and other organisms
 Virtually permanent
 Efficiency, greater ability to search their prey
 Improved quality of produce
 Compatible with most of the IPM components

4. Biological control is "the action of parasites, predators, or pathogens in maintaining
another organism's population density at a lower average than would occur in their
absence".
Van den Bosch et al. (1982) -modified the terms somewhat and referred to:
 Applied biological control as the "manipulation of natural enemies by man to
control pests”
 Natural biological control as that "control that occurs without man's intervention"

5. History and development of biological control and classical examples
of biological Control
900 AD- First use of red ant, Oecophyllasmaragidna to control leaf chewing
insects on mandarin trees
1200 AD-Ants were used for control of date palm pests in Yemen (south of Saudia Arabia).
-Usefulness of ladybird beetles recognized in control of aphids and scales
1726- The first insect pathogen was recognized by de Reaumur. It was a Cordyceps fungus
on a noctuid
1762 - Indian mynah bird, Gracula religiosa exported from India to Mauritius to control red
locust, Nomadacris septemfasciata
1776- Control of the bedbug, Cimex lectularius, was successfully accomplished by release
of the predatory pentatomid ,Picromerus bidens in Europe

6.  1920 - A parasitoid Aphelinus mali introduced from England into India to control Woolly
aphid on Apple, Eriosoma lanigerum.
 1929-31 - Rodolia cardinalis imported into India (from USA) to control cottony cushion
scale Icerya purchasi on Wattle trees.
 1947- The Commonwealth Bureau of Biological Control (CBBC) was established
 1951- CBBC renamed as Commonwealth Institute for Biological Control (CIBC).
Headquarters are currently in Trinidad, West Indies.
 1962- The CILB changed its name to the Organisation Internationale de Lutte
Biologique contre les Animaux et les Plants Nuisibles.
Also known as the International Organization for Biological Control (IOBC).

7. 11
Three approaches to biological contr ol
1. CONSERV
ATION OF NATURAL ENEMIES: Actions that preserve and
increase NE by environmental manipulation. e.g. Use of selective insecticides,
provide alternate host and refugia for NE.
2. CLASSICAL BIOLOGICAL CONTROL: The control of a pest species by
introduced natural enemies (Mainly to control the introduced pest)
3. AUGMENTATION OF NATURAL ENEMIES: Propagation (mass culturing)
and release of NE to increase its population. Two types,
(i) Inoculative release: Control expected from the progeny and subsequent
generations only.
(ii) Inundative release: NE mass cultured and released to suppress pest
directly e.g. Trichogramma sp. egg parasitoid, Chrysoperla carnia predator

8. Steps in Classic Biological Control
1.
2.
3.
4.
5.
6.
7.
Evaluate the pest problem
Foreign exploration
Selection
Quarantine processing
Mass propagation
Field colonization (release)
Evaluation of impact
100 successes in the past 100years!!

9. Biocontrol agents employed in Biological control programme
A. Predator - An animal that feeds upon other animals (prey) that are either smaller or
weaker than itself
Characteristics ofPredators
 An immature predator will consume a number of prey in the process of completing
development to the adult stage.
 The predator is free living in all life stages except the egg.
 The eggs are usually laid in the vicinity of the prey.
 Upon hatching from the egg, predator nymphs or larvae actively seek out, capture,
kill, and consume prey.
 Many predators are carnivorous in both the immature and adult stages (but there are
exceptions [e.g., syrphid flies]).

10. Potential Insect Predators
Order Family Species Hosts
Coleoptera Coccinellidae Cryptolaemus montrouzieri Aphids, Scales,
Mealybugs,
Eggs of lepidopterans
Rodalia cardinalis
Cheilomenes sexmaculata
Harmonia octomaculata
Chilocoris nigrata
Scymnus coccivora
Parascymnus horni
Coccinella transversalis
C. montrouzieri R. cardinalis C. septempunctata C. sexmaculata S. coccivora

11. Cicindelidae Cicindella sexmaculata Aphids, Scales, Mealybugs,
Eggs of lepidopterans
Carabidae Cosnoidea indica,
Anthia sexguttata
Aphids, Scales,
Mealybugs,
Eggs of lepidopterans
Odonata Dragon fly and damsel flies Caterpillars
Mantodea Mantis religiosa Caterpillars and Grasshoppers
Contd
…
Dragonfly Mantis religiosa Anthia sexguttata Asilus sp. Ischiodon scutellaris

12. Contd
…
C. zastrowi arabica C. lividipennis
Order Family Species Hosts
Neuroptera Chrysopidae Chrysoperla zastrowi arabica Aphids, Scales,
Mealybugs, Eggs of
lepidopterans
Hemerobiidae Micromus igoratus
Hemiptera Miridae Cyrtorrhinus lividipennis Hemipterans
Ruduviidae Platymeris laevicollis Grubs
Pentatomidae Eucanthecona furcelleta Caterpillars
Lepidoptera Epipyropidae Dipha aphidivora Aphids
Diptera Asilidae Asilus sp Small insects
Syrphidae Ischiodon scutellaris Small insects
Dipha aphidivora Micromus igoratus

13. Field applications…..
Species Host/s quantity
Cryptolaemus montrouzieri mealybugs 3000-4000/ha
Rodalia cardinalis Aphids/scales/mealy bugs 3000-4000/ha
Chilocoris nigrata Aphids/scales/mealy bugs 3000-4000/ha
10-12/plant
Chrysoperla zastrowi arabica Aphids/scales/mealy bugs/
Eggs of lepidopterans
1.00-1.50 lakh/ha
Micromus igoratus Aphids 5000-6000 /ha
Cyrtorrhinus lividipennis Hemipterans 50-60 bugs/100m2
Dipha aphidivora Aphids 5000-6000 /ha

14. B. Parasitoid: It is a special kind of parasite which often about the same size as its host,
kills its host and requires only one host (prey) for development into a free-living adult.
Characteristics of insect parasitoids:
 Host searching capacity
 Host specificity
 Universal adoptability
 Dispersal ability
 Amenability to mass culture
 Ability to withstand competition
 Ability to out number the pest
 Survival capacity

15. Predators Parasitoids
1. Bigger than the prey 1. Smaller than its host
2. Very active 2. Usually sluggish once the host in
secured
3. Organ of locomotives, sense organ and
mouth parts are well developed.
3. Organ of locomotives, sense organ
and mouth parts not well developed
4. Habitat is independent of its prey. 4. Habitat in same that of its host.
5. Life cycle in longer than the host. 5. Life cycle shorter than the host
6. A single predator may attack several host
in in its life period
6. It usually completes development in a
single host.
V/S
Predator Parasitoids

16. Field applications…..
Species Host/s Quantity
Trichogramma chilonis ESB/INB/OLE 1.50-2.50 Lakh/ha
Trichogramma japonicum YSB/Sl/TSB/OLE 1.50-2.50 Lakh/ha
Trichogramma brasiliensis Ha/OLP 1.50-2.50 Lakh/ha
Goniozus nephanidis CBCP 15-20/plant
Bracon brevicornis CBCP/OLP 25000-50000/ha, 10-15/plant
Bracon bebetor GLM/OLP 25000-50000/ha, 10-15/plant
Chelonus blackburni Ha/Aa/Sl/OLP 25000-50000/ha, 10-15/plant
Cotesia plutellae DBM/OLP 25000-50000/ha, 10-15/plant
Trichospilus pupivora CBCP/OLP 10-15/plant
Tetrastichus israeli CBCP/OLP 10-15/plant
Brachymeria nephantidis CBCP/OLP 10-15/plant
Sturmiopsis inferens ESB/INB/TSB/OLE 250-500 /ha

17. C. Microbial Control
Defined as control of pests by use of microorganisms like viruses, bacteria, protozoa,
fungi, ricketsia and nematodes, which kill their host or debilitate the future generations
Qualities of Insect pathogens…
 Host specificity/suitable strain
 Virulence
 Toxin production
 Rapid Spreading of disease
 Persistent for long time (self-life)
 Amenability to mass culture
 Cost effective and Economical
 Safe to non-target organisms

18. Microbial Agents
I. Entomopathogenic fungi
 Fungi that can act as parasites of insects and kill or seriously disable them
 Over 950 species are pathogenic to arthropods
 20 have been exploited
Symptoms of fungalinfection
 Loss of appetite, irritability and paralyses
 Discoloured patches on integuments and increased acidity in
blood
 The body hardens and covered by dense white mycelial mat
 Mummified larvae adhere to leaves, stem and fruiting body with
upright position on its prolegs at the time of death
 Death occurs with in 4-7 days depending on host insects and
environmental conditions

19. Fungi Target host
Metarhizium anisopliae Green muscardine fungus
Beauveria bassiana White muscardine fungus
White halo fungus
Verticillium lecanii
Nomuraea rileyi
Hirsutella thompsani
Coleopterans, soil
inhibiting pests, BPH,
Grasshoppers
Lepidopetrans,
Coleopterans, leaf hoppers,
plant hoppers, whiteflies
coffee green scale
Sucking pests
Mites
Beauveria Verticillium
Metarhizium Nomurae
a

20. 1. Adhesion of the spore to the
host cuticle
2. Spore germination
3. Penetration of the
cuticle
5. Death and saprophytic
feeding
6. Hyphal reemergence and
sporulation
4. Growth in the hemocoel
Mode of action of entomopathogenic fungi

21. Field applications…..
Fungus Host insect Dosage
Metarhizium anisopliae
Beauveria bassiana
1-2 kg/ac spray
10-15 kg with 50 kg FYM/
vermicompost soil
application
0.4-1.0 kg/ac Foliar spray
Verticillium lecanii 0.4-1.0 kg/ac Foliar spray
Nomuraea rileyi 0.4-1.0 kg/ac Foliar spray
Hirsutella thompsani
White grub, sweet potato
weevil, BPH, DBM, Rhinoceros
beetle, termite, grass hoppers,
caterpillars
Leaf hoppers, plant hoppers,
whiteflies, caterpillars and
DBM
coffee green scale, Leaf and
plant hoppers, coffee berry
borer etc
Leaf eating Caterpillars, S.
litura, H. armigera, T.
archalsia, M. separata, A.
ipsilon etc.
Coconut Mites 1-5 g/ l of water

22. II. Entomopathogenic viruses
 Viruses coming under family Baculoviridae cause disease in lepidoptera larvae.
Two types of viruses are common.
NPV (Nucleopolyhedro virus) e.g. HaNPV, SlNPV GV
(Granulovirus) e.g. CiGV
Mode ofAction

23. Symptoms
 Lepidopteran larva become sluggish, pinkish in colour, lose appetite,
 Body becomes fragile and rupture to release polyhedra (virus occlusion bodies).
 Dead larva hang from top of plant with prolegs attached (Tree top disease or
“Wipfelkrankeit”)
II. Entomopathogenic viruses
NP
V
CPV ( Cytoplasmic
Virus)
G
V

24. Field applications…..
Virus Target pest Crop Dosage
HaNPV H. armigera Tomato, Lablab,
Chickpea, Groundnut,
Sunflower, Tur,
Cotton
250 LE/ha
SlNPV S. litura Groundnut, Tobacco,
Soybean, Crucifers,
Cotton
250 LE/ha
MaNPV M. separata Maize, Sorghum 250 LE/ha
AaNPV A. albistriga Groundnut 250 LE/ha
GV C. infusculetus Sugarcane 250 LE/ha

25. III. Entomopathogenic bacteria
Classification of Entomopha gousbacteria
Spore(Endospore) formers
Obligatory Facultative
Non crystalliferous
Non spore formers
B. Popilliae
P.Japonica
Root grub
B. cereus
Hymenoptera
Coleoptera
Crystalliferous
(toxic)
B. thuringensis
H. armigera
S. litura
Serratia marecescens
Hymenoptera
Lepidoptera

26. Mechanism of action of Bacillus thuringiensis

27. Bt ( Bacillus
thuringiensis)
Bs ( Bacillus
sphaericus)
Pf ( Pseudomonas
fluorescens)
Symptoms of bacterial infection
 Stoppage of feeding
 Regurgitation and diarrhea due to gut paralysis
 Body darkens with dark body fluid, tissue disintegrated and with putrefied
odour

28. IV. Entomopathogenic nematodes (EPNs)
 Nematodes which are capable of killing, sterilizing or seriously hampering the
development of insect and completing at least one stage of their life cycle in the
host.
Other Names: Entomogenous, Entomophilic, Insect parasitic nematodes etc.
Important groups of EPNs
1. Family: Mermithidae :(Order: Enoplida)
2. Family: Steinernematidae (Order; Rhabditida)
3. Family: Heterorhabditidae ( ---- ,,------------)
Steinernem
a
Heterorhabditi
s

29. J3 infective juveniles enter the
blood system of the host through
body openeings
First and second
generation nematodes
develop on the dead host
Infective juveniles leave host
Search for new host
Symbiotic bacteria
released by
nematodes

30. Advantages of microbial agents as component in IPM
 Exploitation for pest control is environmentally safety due to host specificity
 Microorgansims have natural capability of causing epizootic levels due to their
persistence in soil and efficient transmission
 Compatible with chemicals insecticides
 The cost of development and registration of microbial insecticide is much less than
that of chemical insecticides
 Large scale culture and application is relatively easy and inexpensive
 No resistant development

31. Factors affecting biological control
1. Tolerance limit of crop to insect injury - Successful in crops with high tolerance limit
2. Crop value - Successful in crops with high economic value
3. Crop duration - Long duration crops highly suitable
4. Indigenous or Exotic pest - Imported NE more effective against introduced pest
5. If alternate host available for NE, control of target pest is less
6. If unfavourable season occurs, reintroduction of NE required
7. Presence of hyperparasites reduces effectiveness of biocontrol
8. Tritrophic interaction of Plant-Pest-Natural enemy affects success of biocontrol, e.g.
Helicoverpa parasitization by Trichogramma more in tomato than corn
9. Use of pesticides affect natural enemies
10. Selective insecticides (less toxic to NE required)
11. Identical situation for successful control does not occur
12. Depends on life cycle of NE

32. General Limitations of Biological Control include:
 The host (pest) population will continue to exist at a level determined by the properties ofthe
host, its natural enemies and of the habitat they occupy
 The effectiveness of natural enemies must be considered relative to man's economic
thresholds
 The attainment of biological control of one major pest on a crop necessitates the elaboration
of a system of integrated control for other pests of the crop, if any exist; and
 The research necessary in seeking a biological control solution to a problem is often
demanding in terms of scientific and technical staff, funds, and time, and a solution cannot be
guaranteed in advance.