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Question #46594
The Question
An agricultural field heavily infested with a dominant lepidopteran pest is treated exclusively with a biocontrol agent belonging to the genus Nucleopolyhedrovirus. While the target pest population crashes, the overall crop damage eventually returns to pre-treatment levels due to the sudden proliferation of a previously minor sap-sucking insect. Which of the following best explains this ecological phenomenon in the context of Integrated Pest Management (IPM)?
Options
- A.
The biocontrol agent exhibited broad-spectrum toxicity, inadvertently eliminating natural predators of the sap-sucking insect along with the target pest.
- B.
Nucleopolyhedrovirus exhibits high host specificity; eradicating the primary pest caused a competitive release of the secondary pest, demonstrating that IPM requires a synergistic, multi-agent approach.
- C.
The viral agent induced a systemic acquired resistance (SAR) failure in the crop, which inadvertently provided a favorable niche for the secondary sap-sucking pest to thrive.
- D.
Nucleopolyhedrovirus undergoes rapid host-switching in the absence of its primary lepidopteran host, directly parasitizing and increasing the virulence of the sap-sucking insect.
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Evolutionary_Exception
Tackle problems where standard rules evolve or change based on specific environmental constraints.
Concepts Behind This Question
Baculovirus|Nucleopolyhedrovirus|Arthropods|Integrated_Pest_Management
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often memorize that Nucleopolyhedrovirus is 'ideal for IPM' because it is narrow-spectrum and spares beneficial insects.
However, the trap lies in failing to synthesize this with the ecological concept of 'Competitive Release' (NCERT Chapter 13: Organisms and Populations).
An over-reliance on a single highly specific agent removes the dominant competitor, allowing secondary pests to surge, thereby proving that true IPM requires a synergistic, multi-faceted approach rather than a single 'magic bullet'.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Microbes in Human Welfare - Class 12 |
| Concept | Biocontrol Agents Synergy |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |