SSCE BOARD PRACTICALS : 2025 – 2026

PROJECT REPORT
BIOLOGY – 044
NAME : UDAYA KUMAR .P
Roll no:
MICROBES AS BIO-CONTROL AGENT AND
BIOFERTILIZER AND BIO GAS PRODUCTION
 ACKNOWLEDGEMENT

I have taken efforts in this project. However, it

would not have been possible without the kind
support and help of many individuals.
I would like to thank Almighty for keeping my with
sound knowledge to do this project
I would like to thank my Principal and my Biology
teacher for their support in all stages while doing
my project
I would like to thank my parents for their support
and encouragement
I would also like to thank my classmates and
friends for their involvement to do this project
 BONAFIDE CERTIFICATE

This is to be a Bonafide Research work of UDAYAKUMAR .P ; Roll No:

___________________ in Biology -044, entitled
____________________________________________________________

of class XII for SSCE BOARD PRACTICALS – held during the academic year
2025-2026 , It is his/her original work derived from his/her own sincere effort and
enthusiasm

Teacher In-charge Principal

Internal Examiner External Examiner

Index
1. Introduction
2. Microbes Used as Biocontrol Agents
a. Dragonfly
b. Lady Bugs
c. Bacillus thuringiensis as Pest Control
d. Baculovirus
e. Fungus Trichoderma
f. IPM (Integrated Pest Management)
3. Microbes Used as Bio fertilizer

a. Rhizobium
b. Free-living Soil Bacteria
c. Mycorrhiza Association
d. Cyanobacterium
e. Examples of Cyanobacteria: Oscillatoria.

4. Bio gas production : A Vital Gift of Bio

a. Role of Methanobacterium
b. Production Process
c. Functions of IARI and KVIC
d. Pros and Cons of Biogas

5. Conclusion
 Introduction
Microorganisms play a vital role in various applications, including biocontrol agents,
biofertilizers, and biogas production. Biocontrol agents, such as Trichoderma and Bacillus
thuringiensis, are used to control plant pathogens and pests. These microbes produce toxins or
enzymes that inhibit the growth of pathogens, reducing the need for chemical pesticides.
Biofertilizers, like Rhizobium and Azospirillum, enhance soil fertility by fixing atmospheric
nitrogen, promoting plant growth. Mycorrhizal fungi form symbiotic relationships with plant
roots, increasing nutrient uptake. Biogas production involves anaerobic digestion of organic
matter by microbes like methanogens, producing a mixture of methane and carbon dioxide. This
biogas can be used as a renewable energy source. Microbes like Methanobacterium and
Methanococcus are commonly used in biogas production. These microorganisms have
significant potential in sustainable agriculture and energy production. By harnessing the power
of microbes, we can reduce our reliance on chemical fertilizers and fossil fuels. Microbes have
been used in various applications, from food production to environmental sustainability. The
use of microbes in biocontrol agents and biofertilizers can help reduce environmental pollution.
Biogas production is an eco-friendly way to manage organic waste. Microbes play a crucial role
in maintaining ecological balance.
Microbes play a vital role as bio-control agents in sustainable agriculture, offering an eco-
friendly alternative to chemical pesticides. These microorganisms—mainly bacteria, fungi, and
viruses—naturally target and suppress harmful pests, reducing crop damage while preserving
the health of the environment. One prominent example is Bacillus thuringiensis (Bt), a
bacterium that produces toxins lethal to insect larvae but harmless to humans, animals, and
beneficial insects. Fungal bio-control agents like Trichoderma species are also widely used,
especially against soil-borne plant pathogens, due to their ability to outcompete or parasitize
harmful fungi. Similarly, Beauveriabassiana, another fungal species, infects and kills various
insect pests by penetrating their outer surfaces. Viruses like the Nuclear Polyhedrosis Virus
(NPV) are effective against caterpillars, causing fatal infections that spread rapidly among pest
populations. These microbial agents are applied directly to crops or soil and multiply under
suitable conditions to provide long-lasting protection. Their use minimizes chemical residues in
food, protects pollinators, and helps maintain biodiversity. Unlike synthetic pesticides, microbes
target specific pests, reducing the risk of developing resistance. Integrated pest management
(IPM) strategies often include these microbes for efficient, low-risk pest control. Their
continued research and development enhance agricultural productivity and sustainability.
 Dragonflies as Biocontrol Agents;
Dragonflies are natural predators that play a crucial role in controlling mosquito populations and
other insect pests, serving as effective biocontrol agents. They are voracious feeders, consuming
large quantities of mosquitoes, flies, and other insects, making them an eco-friendly and
sustainable solution for pest management. By targeting mosquito populations, dragonflies help
reduce the risk of mosquito-borne diseases such as malaria, dengue fever, and Zika virus.
Additionally, dragonflies can be used in agricultural settings to control insect pests, reducing
crop damage and promoting sustainable agriculture. As a biocontrol agent, dragonflies offer
several advantages, including low maintenance, cost-effectiveness, and environmental
sustainability. By leveraging the natural predatory behavior of dragonflies, we can develop
effective and sustainable pest management strategies that promote ecological balance and
reduce our reliance on chemical pesticides. Overall, dragonflies are a valuable tool in the fight
against insect pests, providing a natural and environmentally friendly solution for pest control.
Dragonflies are also an important part of the ecosystem, serving as both predators and prey for
other animals. Their role in maintaining ecological balance is essential, and their use as
biocontrol agents can have a positive impact on the environment. By promoting the use of
dragonflies as biocontrol agents, we can work towards a more sustainable and environmentally
friendly approach to pest management. This approach can also help to reduce the development
of pesticide-resistant pests, which is a major concern in agriculture. With their effectiveness and
sustainability, dragonflies are an attractive option for those looking for alternative pest control
methods. They can be used in a variety of settings, from agricultural fields to wetlands, making
them a versatile biocontrol agent.
 Lady bug as bio control agents;
Ladybugs are natural predators that play a crucial role in controlling aphid populations and
other soft-bodied insects, serving as effective biocontrol agents. They are voracious feeders,
consuming large quantities of aphids, mites, and other pests, making them an eco-friendly and
sustainable solution for pest management. Ladybugs can be used in agricultural settings to
control aphid populations, reducing crop damage and promoting sustainable agriculture. They
offer several advantages, including low maintenance, cost-effectiveness, and environmental
sustainability. By leveraging ladybugs’ natural predatory behavior, we can develop effective and
sustainable pest management strategies that promote ecological balance and reduce reliance
on chemical pesticides. Ladybugs are a valuable tool in the fight against insect pests, providing a
natural and environmentally friendly solution for pest control. They are widely used in
integrated pest management systems and can be an essential component of sustainable
agriculture practices. Ladybugs contribute to a healthier ecosystem and support biodiversity.
Their effectiveness and sustainability make them an attractive option for farmers and gardeners
seeking alternative pest control methods. By promoting ladybugs as biocontrol agents, we can
work towards a more sustainable approach to pest management.

Fig: Lady bug eating aphid

 Bacillus thuringiensisas pest control agent;
Bacillus thuringiensis (Bt) is a bacterium that produces proteins toxic to certain insect pests,
making it a widely used biocontrol agent. Bt is effective against various pests, including
caterpillars, beetles, and mosquitoes. Its mode of action involves producing crystal proteins
that, when ingested by susceptible insects, disrupt their gut cells, ultimately leading to their
death. Bt is environmentally friendly, as it specifically targets pest species and is generally safe
for non-target organisms, including humans, wildlife, and beneficial insects. This specificity
reduces the impact on biodiversity and ecological balance. Bt-based biopesticides are used in
agriculture, forestry, and public health programs to manage pest populations sustainably. They
offer a valuable alternative to chemical pesticides, contributing to integrated pest management
(IPM) strategies. The use of Bt helps minimize chemical pesticide use, reduce resistance
development in pests, and promote environmentally sustainable practices. Overall, Bacillus
thuringiensis is a key biocontrol agent in sustainable agriculture and pest management.
 Baculoviruses
Baculoviruses, specifically the Nucleopolyhedrovirus genus, are a group of viruses that target
and infect insect pests, making them effective biocontrol agents. They are widely used to
control populations of insects such as caterpillars, beetles, and flies in agricultural and forest
ecosystems. Baculoviruses are environmentally friendly, as they are highly specific to target
pests and generally safe for non-target organisms, including beneficial insects, wildlife, and
humans. This specificity helps maintain ecological balance and biodiversity. Baculovirus-based
biopesticides offer a sustainable alternative to chemical pesticides, reducing the environmental
impact of pest management and contributing to integrated pest management (IPM) strategies.
By using baculoviruses, farmers can effectively manage pest populations while minimizing harm
to the environment and promoting sustainable agricultural practices. Baculoviruses also help
reduce the development of pesticide-resistant pests, further supporting their role in sustainable
pest management. Overall, baculoviruses are a valuable tool in the quest for environmentally
friendly and sustainable pest control solutions.
 Fungus trichoderma;
Trichoderma is a genus of fungi that serves as a potent biocontrol agent, effectively managing
plant diseases and promoting plant growth. It achieves this by parasitizing and killing plant
pathogens, thereby reducing disease severity and enhancing plant health. Trichoderma also
stimulates plant growth and development, leading to improved crop yields and plant vigor. Its
benefits include being environmentally friendly, sustainable, and cost-effective, making it a
valuable tool in sustainable agriculture and plant disease management. By utilizing
Trichoderma, farmers and gardeners can adopt a more natural and eco-friendly approach to
controlling plant diseases and promoting healthy plant growth. This approach supports
integrated pest management strategies and contributes to a healthier ecosystem. Trichoderma's
role in breaking down organic matter and improving soil structure further enhances its utility in
agricultural settings. Overall, Trichoderma is a key component in the pursuit of sustainable
agricultural practices.
IPM ( Integrated pest management
programme);

Integrated Pest Management (IPM) is a holistic approach that combines physical, cultural,
biological, and chemical controls to manage pests sustainably. By considering the ecosystem as
a whole, IPM aims to minimize economic, environmental, and health impacts. This approach
promotes ecological balance, preserves biodiversity, and reduces reliance on chemical
pesticides. IPM involves monitoring pest populations, establishing threshold levels, and
integrating multiple control methods. Its benefits include environmental sustainability,
economic savings, and improved public health. By adopting IPM strategies, farmers and pest
management professionals can effectively manage pests while promoting sustainable
agriculture and reducing environmental harm. IPM is a valuable tool for achieving green goals.
 Microbes used as Bio fertilizer;

Microbes play a crucial role in agriculture as biofertilizers, enhancing soil fertility and plant
growth. Beneficial microorganisms such as Rhizobia, Azospirillum, and Azotobacter fix
atmospheric nitrogen, making it available to plants. Mycorrhizal fungi form symbiotic
relationships with plant roots, improving nutrient uptake and water absorption. These microbes
promote sustainable agriculture by reducing reliance on chemical fertilizers, enhancing soil
health, and increasing crop yields. Biofertilizers are eco-friendly, cost-effective, and contribute
to environmentally sustainable practices. By harnessing the power of beneficial microbes,
farmers can improve soil fertility, promote plant growth, and reduce the environmental impact
of agriculture. This approach supports sustainable agricultural practices and contributes to a
healthier ecosystem.
 Rhizobium and it’s association with plants;
Rhizobium is a genus of bacteria that forms symbiotic relationships with leguminous plants,
such as beans, peas, and lentils. These bacteria colonize the plant’s roots, forming nodules
where they convert atmospheric nitrogen (N2) into a form that the plant can use, such as
ammonia (NH3). This process is known as nitrogen fixation. In return, the plant provides the
bacteria with carbohydrates and other nutrients. Rhizobium plays a crucial role in sustainable
agriculture by:

1. *Enhancing soil fertility*: By fixing atmospheric nitrogen, Rhizobium reduces the need for
synthetic fertilizers.

2. *Promoting plant growth*: Nitrogen fixation supports healthy plant growth and
development.

3. *Supporting eco-friendly practices*: Rhizobium-based biofertilizers offer a natural and

environmentally friendly alternative to chemical fertilizers.

Overall, Rhizobium is a valuable microorganism in sustainable agriculture, contributing to

improved soil health, increased crop yields, and reduced environmental impact.
 Free living soil bacteria
Azospirillum and Azotobacter are beneficial bacteria that promote plant growth and soil health.
Azospirillum fixes atmospheric nitrogen and produces plant growth-promoting substances,
enhancing root development and plant growth. Azotobacter also fixes nitrogen and produces
growth-promoting substances like auxins and gibberellins, while exhibiting biocontrol properties
against certain pathogens. Both bacteria are used as biofertilizers, contributing to sustainable
agriculture by reducing reliance on chemical fertilizers and improving soil health. By harnessing
their potential, farmers can enhance crop yields, promote eco-friendly practices, and support
environmentally sustainable agriculture. These beneficial microbes play a vital role in
maintaining soil fertility and promoting plant health.
 Mycorrhiza association
Mycorrhiza is a symbiotic relationship between fungi and plant roots, enhancing nutrient and
water absorption. Glomus is a genus of arbuscularmycorrhizal fungi that forms associations with
plant roots, improving nutrient uptake, drought tolerance, and soil health. Mycorrhizal fungi like
Glomus:

1. Increase nutrient absorption (phosphorus, nitrogen)

2. Enhance water uptake and drought tolerance

3. Improve soil structure and fertility

4. Support plant growth and development

Glomus species are widely used as biofertilizers, promoting sustainable agriculture and reducing
reliance on chemical fertilizers. By forming mycorrhizal associations, plants can benefit from
improved nutrient acquisition and stress tolerance, leading to healthier and more resilient
crops.
 Cyanobacteria and it’s benefits

Cyanobacteria such as Nostoc, Anabaena, and Oscillatoria are prominent examples of nitrogen-
fixing microorganisms that significantly enhance soil fertility and promote plant growth. By
converting atmospheric nitrogen into a form that plants can utilize, these cyanobacteria play a
crucial role in reducing the reliance on synthetic fertilizers. As effective biofertilizers, they
support sustainable agricultural practices, improve soil health, and contribute to eco-friendly
farming methods. Their ability to fix nitrogen not only boosts crop yields but also helps in
maintaining environmental balance, making them invaluable in the pursuit of sustainable and
environmentally conscious Agriculture.
 Example of cyanobacteria: oscillatoria
Oscillatoria is a genus of cyanobacteria known for its ability to fix atmospheric nitrogen,
contributing to soil fertility and plant growth. It is commonly found in aquatic environments and
soil. Oscillatoria's nitrogen-fixing capability makes it a valuable microorganism in sustainable
agriculture, promoting eco-friendly practices and reducing reliance on synthetic fertilizers. Its
use as a biofertilizer supports environmentally sustainable farming methods, enhancing crop
yields while minimizing environmental impact. Oscillatoria's role in nitrogen fixation highlights
the potential of cyanobacteria in improving soil health and promoting sustainable agriculture.
 Bio gas production : A vital gift of biology
Biogas production is a process that converts organic waste into a renewable energy source. It
involves the anaerobic digestion of biomass, such as agricultural waste, food waste, or sewage
sludge, by microorganisms. This process produces a mixture of methane and carbon dioxide,
known as biogas, which can be used as a sustainable fuel for:

1. Electricity generation

2. Heating

3. Cooking

4. Vehicle fuel

Biogas production offers several benefits, including:

1. Renewable energy source

2. Waste management

3. Reduced greenhouse gas emissions

4. Energy self-sufficiency

Biogas technology has gained attention globally due to its potential to mitigate climate change,
promote sustainable agriculture, and support rural development.
Role of methanobacterium in bio gas production
Methanobacterium is a crucial genus of methanogenic archaea in biogas production, converting
carbon dioxide and hydrogen into methane through anaerobic digestion. This process supports
renewable energy generation, sustainable waste management, and reduced greenhouse gas
emissions. By producing methane, Methanobacterium enables the creation of a valuable energy
source for heating, electricity, and other applications.

Methanobacterium’s role in biogas production is vital for efficient energy generation. It thrives
in anaerobic environments, such as biogas reactors, where it breaks down organic matter. This
process not only produces biogas but also reduces the environmental impact of organic waste.
Methanobacterium’s unique metabolic processes make it an essential microorganism in
anaerobic digestion systems.

The use of Methanobacterium in biogas production contributes to a sustainable energy future.

It helps reduce reliance on fossil fuels and mitigates climate change by utilizing organic waste as
a resource. Methanobacterium’s ability to produce methane from waste materials makes it a
valuable component of biogas technology.

By harnessing the potential of Methanobacterium, biogas production can be optimized,

providing a clean and renewable energy source. This approach supports environmentally
friendly practices and promotes sustainable development. Methanobacterium’s role in biogas
production highlights the importance of microorganisms in addressing energy and
environmental challenges.
 Bio gas production process
Biogas production involves anaerobic digestion of organic matter, typically through these steps:

1. *Feedstock collection*: Gathering organic waste (e.g., agricultural waste, food waste, sewage
sludge).

2. *Pre-treatment*: Preparing the feedstock for digestion (e.g., grinding, mixing).

3. *Anaerobic digestion*: Microorganisms (like Methanobacterium) break down organic matter

in the absence of oxygen, producing biogas (CH4 and CO2).

4. *Biogas collection*: Capturing the produced biogas.

5. *Biogas purification*: Removing impurities (e.g., H2S, CO2) to increase methane content.

6. *Energy generation*: Using biogas for electricity, heat, or fuel.

This process reduces waste, generates renewable energy, and supports sustainable practices.
 Function of IARI and KVIC
*IARI (Indian Agricultural Research Institute)*:

IARI is a premier agricultural research institute in India that focuses on developing sustainable
agricultural practices, improving crop varieties, and enhancing soil health. Its functions include:

- Conducting research on crop improvement, soil science, and agricultural technology.

- Developing high-yielding crop varieties and sustainable farming practices.

- Providing training and education in agricultural sciences.

- Collaborating with national and international institutions to advance agricultural research.

*KVIC (Khadi and Village Industries Commission)*:

KVIC is a statutory body that promotes rural industries, including biogas production, under
India’s Ministry of Micro, Small and Medium Enterprises. Its functions include:

- Promoting and developing rural industries, such as biogas, khadi, and village industries.

- Providing financial support, technical guidance, and training to rural entrepreneurs.

- Encouraging sustainable and eco-friendly industries that generate employment in rural areas.

- Implementing programs to support rural development and self-employment opportunities.

Both IARI and KVIC play crucial roles in promoting sustainable agriculture and rural
development in India.
 Pros and cons of bio gas production
* of Biogas Production:*

1. *Renewable Energy Source*: Biogas is a sustainable and renewable energy source produced
from organic waste.

2. *Waste Management*: It helps in managing organic waste, reducing landfill use, and
minimizing environmental pollution.

3. *Reduced Greenhouse Gas Emissions*: Biogas production captures methane that would
otherwise be released into the atmosphere, reducing greenhouse gas emissions.

4. *Energy Independence*: Biogas can be used locally, reducing dependence on fossil fuels and
enhancing energy security.

5. *Economic Benefits*: Biogas production can create jobs and generate income in rural areas
through the sale of energy and biofertilizers.

6. *Soil Fertility*: The digestate (residue from biogas production) can be used as a nutrient-rich
biofertilizer, improving soil health.

*Cons of Biogas Production:*

1. *High Initial Costs*: Setting up biogas plants requires significant investment in infrastructure
and technology.

2. *Feedstock Quality and Availability*: Biogas production depends on the consistent availability
and quality of organic waste, which can vary.

3. *Technical Challenges*: Biogas production requires careful management of anaerobic

digestion processes, which can be technically complex.

4. *Potential for Odor and Emissions*: If not properly managed, biogas production can lead to
unpleasant odors and methane emissions.

5. *Scalability Issues*: Large-scale biogas production may face challenges in feedstock collection
and logistics.

6. *Regulatory and Policy Framework*: The success of biogas production can depend on
supportive policies and regulations, which may vary by region.
Overall, biogas production offers significant environmental and economic benefits but requires
careful planning, management, and investment to overcome its .
 Conclusion
Microbes play a pivotal role in sustainable development through their applications in biocontrol
agents, biogas production, and biofertilizers. By harnessing the potential of microbes like
Trichoderma, Pseudomonas, Methanobacterium, Rhizobium, and Azospirillum, we can promote
eco-friendly practices, reduce reliance on chemical pesticides and fertilizers, and generate
renewable energy. These microbial applications contribute to sustainable agriculture,
environmental protection, and energy security, ultimately supporting a healthier planet and a
more sustainable future. By leveraging microbial technology, we can address pressing global
challenges and foster a more environmentally conscious approach to development.
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