Microbes as Biocontrol Agents - Unsolved Practice Set
Chapter: Microbes in Human Welfare | Topic: Microbes as Biocontrol Agents
MICROBES AS BIOCONTROL AGENTS - UNSOLVED PRACTICE SET
Topic: Microbes as Biocontrol Agents
Multiple Choice Questions
Q1. Biocontrol refers to the use of:
- Chemical pesticides to control pests
- Living organisms to control plant diseases and pests, reducing dependence on harmful chemicals
- Genetically modifying only the pest species
- Only mechanical pest traps
Q2. Bacillus thuringiensis (Bt) is widely used as a biocontrol agent because it produces a toxin that is effective against:
- Weeds
- Certain insect larvae, such as those of the butterfly/moth family
- Bacteria only
- Fungal spores only
Q3. Trichoderma species are commonly used as biocontrol agents mainly to protect plants against:
- Insect pests only
- Several plant pathogens (disease-causing fungi)
- Bird damage
- Excess sunlight
- Q4. Baculoviruses, used as biocontrol agents, are considered advantageous because they are generally:
- Broad-spectrum and harmful to all organisms
- Species-specific (narrow-spectrum) and unlikely to harm non-target organisms
- Effective against bacteria only
- Toxic to plants
Q5. One major benefit of using microbial biocontrol agents instead of chemical pesticides is that they:
- Increase environmental pollution significantly
- Help reduce our dependence on harmful chemical pesticides, benefiting the environment
- Are always more expensive with no other advantages
- Have no effect on pest populations at all
Short Answer Questions
Q6. Define biocontrol, and explain why it is considered an environmentally friendly approach to pest management.
Q7. Name the bacterium used to produce a toxin effective against insect larvae, and mention how this has been applied in genetically modified crops.
Q8. What role does Trichoderma play as a biocontrol agent in agriculture?
Q9. Why are baculoviruses considered particularly safe biocontrol agents compared to broad-spectrum chemical pesticides?
Long Answer Questions
Q10. Discuss the use of microbes as biocontrol agents in agriculture, explaining how organisms like Bacillus thuringiensis and Trichoderma help manage pests and plant diseases.
Q11. Explain the advantages of using microbial biocontrol agents over chemical pesticides, considering both environmental and ecological factors.
APPLICATION / ANALYSIS
Q12. A cotton farmer switches from using chemical pesticides to planting Bt cotton, a genetically modified crop that produces a bacterial toxin effective against certain insect pests. Explain, using your understanding of biocontrol, how this shift could reduce both pest damage and environmental harm.
Q13. A farmer using a broad-spectrum chemical pesticide against a crop pest also notices a decline in beneficial insects like pollinators in the same field. Explain how switching to a species-specific biocontrol agent, such as a baculovirus, could avoid this particular problem.