Biocontrol Agents: Overview, Types, Merits and Demerits

What are Biocontrol Agents?

Biocontrol agents prevent pests or insects from reproducing by using their natural enemies. Biological control is the process by which biocontrol agents operate. The use of naturally occurring strains of any microorganisms or genetically modified organisms to reduce the severity of diseases caused by plant pathogens is known as a "biocontrol agent" (BCA). Some basic facts about biocontrol agents are discussed below:

• Biocontrol is the use of a living organism or biological agent to stop the growth of an insect or other pest.

• The biocontrol agents defend plants from pests, bacteria, predators, and other natural enemies.

• They aid in reducing plant pest infestations caused by weeds, nematodes, insects, and mites.

• The biological control agents target harmful organisms only, and they leave the beneficial organisms in the soil alone.

Types Of Biocontrol Agents

Two categories of biological control exist:

1. Classical biocontrol (Importation)

2. Inductive Biocontrol (Augmentation)

These types are based on the method of introducing or enhancing natural enemies of pests. In classical biocontrol, new beneficial organisms are imported, while in inductive biocontrol, the population of existing agents is increased to control pests.

Characteristics of Biocontrol Agents

Biocontrol agents are natural and eco-friendly. They do not harm humans, animals, or crops. These agents help maintain balance in ecology and reduce the need for chemical pesticides. Some basic characteristics of biocontrol agents are:

• It is a natural way to manage insects, weeds, pests, and other living things that hinder growth. It is applied to raise crop production and yield.

• Predation and parasitism are the basic biological control principles. Trichoderma, Baculoviruses, and Nucleopolyhedrovirus are a few of the microbes used as biocontrol agents.

• Farmers use biocontrol agents to kill only undesirable organisms that afflict plants with disease because chemical fertilizers can occasionally kill the desired and necessary soil organisms.

• Pest management and the life cycle of the pest are necessary to understand how to approach the biological control process.

• Spraying a plant with BT solution made from seeds will kill the caterpillars of butterflies.

• Toxins from the worms' intestines are released by the dried seeds, killing them.

Various Biocontrol Agents

Common biocontrol agents include bacteria, fungi, viruses, and insects. Each plays a specific role in suppressing pests and plant diseases. Examples of biological pest control agents are provided below:

Types of Questions Asked from Biocontrol Agents

During exam preparation, different types of questions about the Biocontrol Agents are asked. The table below contains the different patterns of questions asked in different exams.

Tips, Tricks, and Strategies for Biocontrol Agents

It takes effort to remember everything in a single go. We made the entire problem easy. Some of the tricks regarding Biocontrol Agents are given below which you can use to memorize the important points.

Types of Biocontrol Agents

"FPBVP: Fungi, Predators, Bacteria, Virus, Parasitoids"
F: Fungi (e.g., entomophagous fungi to control aphids)
P: Predators (e.g., spiders, dragonflies, lacewings)
B: Bacteria (e.g., Bacillus thuringiensis for pest control)
V: Virus (host-specific viruses targeting pests)
P: Parasitoids (e.g., parasitic wasps laying eggs in host insects)

Categories of Biocontrol

"CI: Classical, Inductive"
C: Classical biocontrol (prey-predator relationships, using natural enemies)
I: Inductive biocontrol (augmentation, using pathogens like nematodes)

Advantages of Biocontrol

"LESS: Low-risk, Eco-friendly, Sustainable, Specific"
L: Low-risk to human health and environment
E: Eco-friendly (minimizes chemical pesticide use)
S: Sustainable over long periods
S: Specific (targets only the pest)

Steps in Biocontrol Implementation

"ISAT: Introduction, Selection, Application, Testing"
I: Introduction of biocontrol agents
S: Selection of suitable agents for specific pests
A: Application in the field (release of agents)
T: Testing for effectiveness and monitoring progress

MCQs on Biocontrol Agents

Q1. When a natural predator (living organism) is applied to the other pathogen organisms to control them, this process is called?

1. Biological control

2. Genetic engineering

3. Artificial control

4. Confusion technique

Correct answer: 1) Biological control

Explanation:

Biological control of pests and diseases - There is a method of controlling pests that relies on natural predation rather than introduced chemicals. A natural technique called biological control employs other living things to manage pests including weeds, insects, mites, and other agents that cause plant diseases. It depends on organic processes like herbivory, parasitism, and predation.

Hence, the correct answer is Option 1) Biological control.

Q2. Insect harms most crops in the ground. It can be prevented by

1. By using insect repellent

2. By eliminating breeding area

3. Plant breeding

4. More than one correct answer

Correct answer: 4) More than one correct answer

Explanation:

1. Applying insect repellent: By keeping pests at bay or eliminating them, insecticides and repellents help shield crops from insect damage.

2. Getting rid of breeding grounds: You can lower the number of insects and avoid damage by getting rid of weeds, standing water, and other places where they breed.

3. Plant breeding: Plant breeding can reduce the susceptibility of crops to insect infestations by creating crop varieties that are resistant to pests.

There are multiple right answers because all of these techniques help to lessen insect damage.

Hence, the correct answer is option 4) More than one correct answer.

Q3. Select the correct group of biocontrol agents:

1. Bacillus thuringiensis , Tobacco mosaic virus , Aphids

2. Trichoderma, Baculovirus, Bacillus thuringiensis

3. Oscillatoria , Rhizobium , Trichoderma

4. Nostoc , Azospririllum, Nucleopolyhedrovirus

Correct answer: 2) Trichoderma, Baculovirus, Bacillus thuringiensis

Explanation:

Trichoderma is a highly effective biocontrol agent extensively used to manage soil-borne diseases by suppressing the growth of pathogenic fungi. Baculovirus is a biological control agent with narrow insecticidal properties, specifically targeting and killing insects and arthropods without harming other organisms. Bacillus thuringiensis is a naturally occurring, spore-forming soil bacterium that produces protein crystals toxic to specific insects, making it an important tool for pest management in agriculture.

Hence, the correct answer is option 2)Trichoderma, Baculovirus, Bacillus thuringiensis

Also Read:

• MCQs on Microbes as Biocontrol Agents

• Biogas

• Biofertilizers

Frequently Asked Questions (FAQs)

Q1. What is an example of biological control of microbes?
Using Trichoderma fungus to control plant pathogens is an example of biological control.

Q2. What are the three types of biological control agents?
The three types are predators, parasitoids, and microbial pathogens.

Q3. What is the role of microorganisms in biological control of pests?
Microorganisms like bacteria, fungi, and viruses infect or kill pests, reducing their population naturally without harming crops.

Q4. What are the 3 microbes used for controlling pollution?
Pseudomonas, Methylobacterium, and Alcaligenes are microbes commonly used in pollution control.

Q5. Which method is most effective for microbial control?
Sterilization is the most effective method, as it completely kills all microbes, including spores.