Bio pesticides by Azmi Ahala_20241111_141637_0000.pdf

Biopesticides and their effects on plants

1. VIRAL AND
FUNGAL
PESTICIDES
Azmi ahala k
1st msc microbiology

2. BIOPESTICIDES
1.microbial biopesticides
2.
3.biochemical biopesticides
plant -incorporated biopesticides
Biopesticides are natural substances derived from plants,
microorganisms, or minerals used to control pests and diseases in
agriculture. They are often more environmentally friendly than
synthetic pesticides and can be specific to certain pests, reducing
harm to beneficial organisms. Common types include:

3. MICROBIAL
BIOPESTICIDES
1
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2
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3
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4
Bacterial biopesticides
viral biopesticides
fungal biopesticides
protozoan biopesticides
Microbial biopesticides are derived from natural microorganisms, such
as bacteria, fungi, or viruses, that target and control pests and diseases
in agriculture. They work by various mechanisms, including pathogen
inhibition, competition for resources, and production of toxins harmful to
specific pests.
types

4. VIRAL BIOPESTICIDES
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Viral biopesticides are a type of biopesticide that utilize viruses to control
pest populations.
These viruses typically infect specific insects and can lead to their death or
reduced reproductive capacity.
Viral biopesticides are particularly attractive due to their host specificity.
•These viruses infect pests, replicate within them, and cause
lethal diseases, ultimately reducing pest populations.
•They are typically applied in the same manner as chemical pesticides,
through spraying or other delivery systems, to infected areas or crops.

5. •Baculovirus Viruses of group baculovirus are the most potential
biocontrol agent. They are highly specific and can quickly infect
large populations of insects.
•The baculoviruses (family: Baculoviridae) are a group of large DNA
viruses that infect insects. These viruses are well known for their
utility and versatility as gene expression vectors, biological
pesticides, and vectors for transduction of mammalian cells .
The nucleopolyhedrosis Virus (NPV)are used for insect control on a
commercial.
•
•Another baculoviruse,the granulosis viruses(GV), si also promising
and may achieve a commercial status for Spodoptera litura control in
india
Baculoviruses

8. 01
Nuclear polyhedrosis viruses(NPV)
•
After ingesting the poly hydra,larvae show no outward
symptoms for 4 days to 3 weeks
02
•The polyhydrin protein dissolves in the alakaline environment of
the new host’s gut and the occluded virus is released
NPV viruses develop in the host cell(larvae) nucleus
This virus infects the gut epithelialcells and virus replication
takes place
•
•
•virus then produced and budded from the infected gut cell
•At this time,the larval skin darkensand larvae climb to the
highest point on their host plant where they die

14. Granulovirus(GV)
•A granulovirus specifically affecting the indian meal moth
•modern powder formulation can be applied to commodities as a
spray or dust
•The granulovirus can provide economic control of the
indianmeal moth
•Granuloviruses can be an effective tool for managing pest
populations in agriculture, offering an environmentally friendly
alternative to chemical pesticides.
•Develop either in the nucleus/cytoplasm/
•tracheal matrix / epithelial cells of host
•Virions are occluded singly in small inclusion
•
bodies called capsule

15. Rod shaped virion, Ds DNA
• Oval occlusion bodies about 200x400nm
• They enter through ingestion, similar to NPV
• Fat body is the major organ invaded
• Diseased larvae - less active, flaccid, fragile, wilted prone to

16. MECHANISM
•Replication of virus occurs in the nuclei or cytoplasm of the
target cell
The expression of viral proteins occurs in 3 phases -early
phase,late phase,very late phase
•
•it is the late phase the virions assemble as the occlusion body
protein is synthesized
vireons of NPV occluded with each occlusion body to develop
polyhedra where as the gv virion is occluded in a smallocclusion
to generategranules
infected nucei can produce100s of polyhedra and1000s of
granules per cell
This can create enzootic,deplete the pest population and
ultimately create significant impacton the on the economic
threshold of the pest
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•

18. FUNGAL BIOPESTICIDES
Fungal biopesticides are biological control agents derived from fungi that
are used to manage pests and diseases in agriculture. They are part of a
broader category of biopesticides, which also includes bacteria, viruses,
and plant extracts. Fungal biopesticides can effectively target specific
pests while being less harmful to non-target organisms and the
environment.
Most widely used species include:-
1.
2.Metarhizium anisopliae
3.Verticillium lecanii
4.Nomurea rileyi
5.paecilomyces farinosus
Beauveria bassiana

19. verticillium lecanii
•
A naturally occurring fungus with potential as a biocontrol agent
against specific insect pests.
•it is also known as ‘white - halo’fungus because of the mycilial
growth on the edges of infected scale insects
Effective against soft-bodied insects, including aphids, whiteflies,
and thrips.
Infects pests through the cuticle, leading to fungal growth within
the host and subsequent death.
•
•
•Generally safe for non-target organisms, including beneficial
insects, humans, and the environment.
Can be applied as a spray, granule, or through soil
incorporation, allowing flexibility in pest management strategies.
: Contributes to sustainable agriculture by providing an eco-
friendly alternative to synthetic pesticides.
•
•

20. Beauveria bassiana
•A naturally occurring entomopathogenic fungus that targets
various insect pests.
Effective against a wide range of insects, including aphids,
whiteflies, thrips, and beetles.
•
•Infects insects through their cuticle, producing enzymes that
penetrate and colonize the host, leading to its death.
•Generally considered safe for non-target organisms, including
beneficial insects, wildlife, and humans.
•Can be applied as a spray or granule; also compatible with
various delivery systems in agriculture.

21. Metarhizium anisopliae
•Entomopathogenic fungus targeting insect pests.
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•
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Spores attach to the insect, penetrate the cuticle, and proliferate
internally.
Effective against aphids, whiteflies, beetles, etc Reduces
reliance on chemical pesticides
Can be applied via soil, foliage, or in integrated pest
management (IPM).
•Generally safe for humans, animals, and the environment when
used properly.
•Metarhizium anisopliae

22. ENTER TITLE

23. ENTER TITLE
Numurea rileyi
•Numurea rileyi is a species of fungus known for its potential in
pest management.
It serves as a natural alternative to synthetic pesticides,
promoting sustainable agriculture.
•
•It may produce bioactive compounds that exhibit insecticidal or
antifungal properties
•Offers reduced toxicity to non-target organisms and minimal
environmental residue compared to chemical pesticides.

25. BIOMASS PRODUCTION
Beauveria bassiana, Meturrhizum anisoplige and Acrostalagmus aphidum can all be
grown in semi- solid fermentation.
The media and procedures are similar to those employed in the Bacillus thuringiensis
semi-solid fermentation.
Here, a liquid inoculum is used to inoculate the bran, and many media have been
developed. Many fungi prefer corn meal to bran in the medium.
Semi-solid production medium contains more corn meal than in the inoculum
medium.
In other words, it is necessary to replace about half the bran in the formulation with
corn meal.
Since the developing mycelium binds the bran medium tightly, it is usually necessary
for maximum yields to mix the fermenting bran once or twice before sporulation
begins. To obtain sporulation after the mycelium is well developed, drying of
cultures should be done as quickly as possible.

26. The semi-solid fermentation is preferable for most of these fungi, since
conidia need not be recovered from the bran base. The dry conidia-bran
mixture is relatively stable, but cannot be stored for prolonged periods of
time.
At present, submerged fermentation is not used in mass production of
fungal pathogens. The reason behind this is the failure of many
entomopathogenic fungi to produce true conidia. Vezina et al. (1965) have
reported the production of true conidia by an insect pathogenic fungus
Aspergillus ochraceus.
Blastospores obtained in a submerged culture are difficult to preserve and
tend to lose their viability easily. The submerged cultivation of the fungal
insect pathogens would be more useful if true conidia could be obtained.
Much research work needs to be done in this area

27. Advantages of fungal pesticides
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Fungal insecticides are often species-specific, they primarily
affect the target pest without harming non-target organisms.
They are biodegradable and tend to have minimal
environmental impact compared to chemical pesticides.
Fungi can persist in the environment and continue to infect
pests over time, offering long-term control.
Insects are less likely to develop resistance to fungal pathogens
compared to chemical pesticides.

28. •
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Fungal insecticides can be sensitive to environmental
conditions like temperature, humidity, and sunlight, which may
limit their effectiveness.
Fungi often take longer to kill pests compared to chemical
insecticides, which can be a disadvantage in urgent pest control
situations.
Fungal insecticides typically affect only specific pests, which
limits their broad-spectrum control.
Some fungal agents need to be stored carefully (e.g.,
refrigerated) to maintain their viability.
Disadvantages of fungal biopesticides

29. References
•Industrial microbiology -A H Patel
•management of insect pests -B Ramanujam
• Google

30. Thank you!