UPSC MainsAGRICULTURE-PAPER-II201512 Marks
Q33.

Biological control of pests and diseases

How to Approach

This question requires a comprehensive understanding of biological control methods in agriculture. The approach should be to first define biological control and its importance. Then, categorize different types of biological control agents (microbial, macrobiological, and botanical). Discuss the advantages and disadvantages of each, and highlight recent advancements and challenges. Finally, discuss the role of government and farmers in promoting this sustainable practice. A structured answer with examples will be crucial for scoring well.

Model Answer

0 min read

Introduction

The escalating use of synthetic pesticides poses significant threats to human health, biodiversity, and the environment. Recognizing this, biological control, a sustainable and eco-friendly approach to pest and disease management, has gained prominence. Biological control utilizes living organisms to suppress pest populations, offering a targeted and environmentally sound alternative to chemical interventions. The FAO promotes Integrated Pest Management (IPM) which increasingly incorporates biological control as a core component. Recent advancements in biotechnology and understanding of microbial interactions are further bolstering the efficacy and application of biological control methods, essential for achieving sustainable agricultural practices and contributing to the goal of 'Bhoomi' - healthy soil, healthy crops, and a healthy planet.

What is Biological Control?

Biological control is a method of controlling pests based on natural predation, parasitism, or competition. It’s a core component of Integrated Pest Management (IPM) strategies, aiming to minimize reliance on synthetic pesticides. It leverages natural enemies to keep pest populations below economically damaging levels.

Types of Biological Control Agents

1. Microbial Control

This involves utilizing microorganisms like bacteria, fungi, viruses, and nematodes to control pests. These agents are often host-specific, reducing the risk of non-target effects.

  • Bacteria: Bacillus thuringiensis (Bt) is a widely used bacterium producing toxins that are lethal to specific insect larvae. Bt toxins are incorporated into genetically modified (GM) crops like Bt cotton.
  • Fungi: Beauveria bassiana and Metarhizium anisopliae are fungal pathogens that infect insects and nematodes.
  • Viruses: Baculoviruses are highly specific to insect pests and are increasingly used as biopesticides.
  • Nematodes: Entomopathogenic nematodes like Steinernema and Heterorhabditis parasitize insect larvae.

2. Macrobiological Control

This utilizes larger organisms, such as predators, parasitoids, and pathogens, to control pests.

  • Predators: Ladybugs (predators of aphids), lacewings, and spiders are common examples of predatory insects.
  • Parasitoids: Parasitoid wasps lay their eggs inside insect hosts, eventually killing them. Trichogramma wasps are widely used to control crop pests.
  • Pathogens: These are larger organisms that cause disease in pests, like certain protozoa.

3. Botanical Control

This involves using plant-derived compounds (biopesticides) to control pests. These compounds are often less toxic than synthetic pesticides.

  • Neem: Neem oil, extracted from the neem tree, is a broad-spectrum insecticide, fungicide, and nematicide.
  • Pyrethrum: Derived from chrysanthemum flowers, pyrethrum is a natural insecticide.
  • Rotenone: A natural insecticide derived from the roots of several plants, though its use is restricted due to toxicity concerns.

Advantages and Disadvantages of Biological Control

Aspect Advantages Disadvantages
Environmental Impact Reduced pesticide residues, less harm to non-target organisms, improved soil health. Can be slower acting than chemical pesticides.
Resistance Less likely to induce resistance in pests compared to chemical pesticides. Potential for hyperparasitism (parasitoids attacking beneficial organisms).
Cost Can be cost-effective in the long run, especially with mass production of biocontrol agents. Initial setup costs (e.g., establishing predator populations) can be high.
Specificity Often highly specific, minimizing impact on beneficial insects. May not be effective against a wide range of pests.

Recent Advancements & Challenges

Recent advancements include:

  • Metagenomics: Identifying novel biocontrol agents from soil and plant microbiomes.
  • Genetic Engineering: Developing genetically modified biocontrol agents with enhanced efficacy.
  • Nanotechnology: Formulating biocontrol agents for improved delivery and persistence.
  • Understanding Ecosystem Interactions: Recognizing the complexity of biological control and optimizing strategies based on ecological principles.

Challenges include:

  • Mass Production: Developing cost-effective and scalable mass production techniques for biocontrol agents.
  • Field Efficacy: Ensuring the survival and effectiveness of biocontrol agents under field conditions.
  • Farmer Awareness: Increasing farmer awareness and adoption of biological control practices.

Government Initiatives & Farmer Role

The Indian government promotes biological control through various schemes:

  • National Mission on Sustainable Agriculture (NMSA): Promotes IPM practices, including biological control.
  • Paramparagat Krishi Vikas Yojana (PKVY): Encourages organic farming, which inherently relies on biological control.
  • Central Integrated Pest Management Centre (CIPMC): Provides training and technical support for IPM and biological control.

Farmers need to be educated about the benefits of biological control and provided with access to quality biocontrol agents.

Biological control offers a sustainable pathway towards reducing reliance on synthetic pesticides and promoting environmentally friendly agriculture. While challenges remain in terms of cost, efficacy, and farmer adoption, ongoing research and government support are paving the way for wider implementation. Integrating biological control practices with conventional farming methods through IPM is crucial for ensuring food security while safeguarding the environment and human health. A paradigm shift towards ecologically sound agricultural practices is essential for a resilient and sustainable future.

Conclusion

Biological control offers a sustainable pathway towards reducing reliance on synthetic pesticides and promoting environmentally friendly agriculture. While challenges remain in terms of cost, efficacy, and farmer adoption, ongoing research and government support are paving the way for wider implementation. Integrating biological control practices with conventional farming methods through IPM is crucial for ensuring food security while safeguarding the environment and human health. A paradigm shift towards ecologically sound agricultural practices is essential for a resilient and sustainable future.

Answer Length

This is a comprehensive model answer for learning purposes and may exceed the word limit. In the exam, always adhere to the prescribed word count.

Additional Resources

Key Definitions

IPM (Integrated Pest Management)
A comprehensive approach to pest control that uses a variety of techniques, including biological control, cultural practices, and chemical pesticides, to minimize pest damage while minimizing environmental impact.
Parasitoid
An organism, typically an insect, that lives on or in another organism (the host) and eventually kills it. Parasitoid wasps are commonly used in biological control.

Key Statistics

The global biopesticides market was valued at USD 4.4 billion in 2023 and is projected to reach USD 7.8 billion by 2030, growing at a CAGR of 8.1% from 2023 to 2030. (Source: Allied Market Research)

Source: Allied Market Research

According to the FAO, approximately 40% of global crop production is lost to pests and diseases annually, highlighting the need for sustainable pest management strategies like biological control.

Source: FAO

Examples

Bt Cotton in India

Bt cotton, genetically modified to produce the Bt toxin from *Bacillus thuringiensis*, has significantly reduced insecticide use in cotton cultivation in India, though resistance issues are emerging.

Frequently Asked Questions

What is the difference between biological control and biopesticides?

Biological control is a strategy utilizing living organisms to control pests. Biopesticides are the actual products (e.g., Bt sprays, neem oil) derived from biological sources that are used to implement biological control.

Topics Covered

AgricultureEntomologyPlant PathologyPest ManagementDisease ControlIntegrated Pest Management