Microbes as Biocontrol Agents and Biofertilisers
Bacillus thuringiensis, Trichoderma, Baculovirus, Rhizobium, mycorrhiza and cyanobacteria. (Biology › Microbes in Human Welfare, NEET UG syllabus.)
What is Microbes as Biocontrol Agents and Biofertilisers?
Biological methods of controlling plant diseases and pests using natural enemies, often microbes, to reduce or eliminate the need for chemical pesticides.
Key points
- Define and differentiate between biocontrol agents and biofertilisers.
- Identify key microbial examples for biocontrol and their specific mechanisms of action.
- Identify key microbial examples for biofertilisation and their roles in nutrient cycling.
- Explain the advantages of using microbial agents over chemical alternatives in agriculture.
Common exam trap
Confusing the specific targets or mechanisms of different biocontrol agents (e.g., Bt for insects, *Trichoderma* for fungi).
Definitions
- Term
Biocontrol Agents
- Meaning
Biological methods of controlling plant diseases and pests using natural enemies, often microbes, to reduce or eliminate the need for chemical pesticides.
- Term
Biofertilisers
- Meaning
Organisms that enrich the nutrient quality of the soil by fixing atmospheric nitrogen, solubilizing phosphorus, or stimulating plant growth through the production of growth-promoting substances.
- Term
Integrated Pest Management (IPM)
- Meaning
An ecosystem-based strategy that focuses on long-term prevention of pests or their damage through a combination of techniques such as biological control, habitat manipulation, modification of cultural practices, and use of resistant varieties.
- Term
Nitrogen Fixation
- Meaning
The process by which atmospheric nitrogen (N₂) is converted into ammonia (NH₃) or other nitrogenous compounds by certain microorganisms, making it available for plant use.
- Term
Mycorrhiza
- Meaning
A symbiotic association between a fungus and the roots of a vascular plant, where the fungus helps the plant absorb water and nutrients (especially phosphorus) and receives carbohydrates from the plant.
Learning objectives
Define and differentiate between biocontrol agents and biofertilisers.
Identify key microbial examples for biocontrol and their specific mechanisms of action.
Identify key microbial examples for biofertilisation and their roles in nutrient cycling.
Explain the advantages of using microbial agents over chemical alternatives in agriculture.
Relate the concepts of microbial biocontrol and biofertilisers to sustainable agriculture and environmental protection.
Prerequisites
Basic understanding of microorganisms (bacteria, fungi, viruses).
Knowledge of plant nutrition and nutrient cycles (especially nitrogen and phosphorus).
Basic concepts of ecology, symbiosis, and pest management.
Common mistakes
Confusing the specific targets or mechanisms of different biocontrol agents (e.g., Bt for insects, *Trichoderma* for fungi).
Misunderstanding the symbiotic nature of *Rhizobium* and mycorrhiza.
Forgetting that Baculoviruses are highly species-specific and narrow-spectrum.
Not distinguishing between nitrogen-fixing bacteria (like *Rhizobium*) and phosphorus-solubilizing fungi (like mycorrhiza).
Assuming all microbes are harmful; failing to recognize their beneficial roles.
Keywords
Biocontrol
Biofertilisers
Bacillus thuringiensis
Trichoderma
Baculovirus
Nucleopolyhedrovirus
Rhizobium
Mycorrhiza
Glomus
Cyanobacteria
Anabaena
Nostoc
Nitrogen fixation
Phosphorus solubilization
IPM
Sustainable agriculture
Organic farming
Practice preview
Which of the following is a symbiotic bacterium that fixes atmospheric nitrogen in the root nodules of leguminous plants?…
easy
Baculoviruses are excellent biocontrol agents because they are:…
medium
Mycorrhizal associations are beneficial to plants mainly due to their ability to:…
medium