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.

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:

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.

Importance of Biocontrol Agents in Agriculture

Many farmers use chemical fertilizers to control the pest problems. These harmful chemicals affect human health and create environmental issues like soil pollution. Instead, biocontrol agents provide a much safer option.

Eco-friendly: Biocontrol agents are naturally occurring and they do not harm the ecosystem.

Safe for Humans: Biocontrol agents are non-toxic and have no side effects unlike the harmful chemicals.

Reduced Chemical Use: Using biocontrol agents significantly reduces the need for chemical fertilizers which harm the environment.

Improved Biodiversity: They support the maintenance of agricultural biodiversity by creating a chemical free and favorable habitat for the organisms.

Exam Relevance

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.

Biocontrol Agents NEET MCQs

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

FAQs on Biocontrol Agents

What are biocontrol agents in biology?

Biocontrol agents are living organisms or natural substances used to control pests, diseases, or unwanted species in agriculture and ecosystems. They work by exploiting natural relationships between organisms, such as predation, parasitism, or competition, to reduce the population of harmful organisms without relying on synthetic chemicals.

What are the types of biocontrol agents?

1. Predators: Organisms that directly kill pests. e.g., ladybird beetle feeding on aphids

2. Parasitoids: Insects that lay eggs inside pests, larvae kill the host. e.g., Trichogramma wasps

3. Bacteria: Infect the digestive tract of the pest insect. E.g., Coccobacillus

4. Virus: designed to selectively kill pests without affecting the non-target organisms.

What are the advantages of biocontrol over chemical methods?

• Eco-friendly: Does not pollute soil, water, or air.

• Target-specific: Affects only pests, without harming beneficial organisms.

• Safe for humans and animals: No harmful pesticide residues in food.

• Cost-effective: Reduces repeated pesticide use and preserves soil fertility.

What are the drawbacks of using biocontrol agents?

The drawback of using biocontrol agents is that they do not completely eradicate the pest. Farmers are not knowledgeable about the techniques. They only work for long-term cultivation and may affect the quality of the crops.