Question

Given below are two statements
Statement I: PCR based genotyping techniques are useful to detect susceptible (SS), Resistant (RR) and heterozygous (RS) genotypes which are necessary for effective resistance management
Statement II: Use of genetically engineered crops does not delay the development of resistance.
In light of the above statements, choose the most appropriate answer from the options given below:

• A. Both Statement I and Statement II are correct
• B. Both Statement I and Statement II are incorrect
• C. Statement I is correct, but Statement II is incorrect
• D. Statement I is incorrect, but Statement II is correct

Hint:

Transgenic Bt crops express toxins continuously, which accelerates resistance development through constant selection pressure unless a mandatory non-Bt refuge strategy is implemented.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
Insect Resistance Management (IRM) is crucial to preserving the efficacy of chemical insecticides and transgenic crops.
It relies on molecular monitoring tools and ecological strategies to manage resistance alleles in pest populations.

Step 2: Detailed Explanation:
Let us evaluate both statements:
- Statement I: PCR-based molecular assays (such as AS-PCR or qPCR) are highly sensitive techniques used to identify point mutations or alleles associated with resistance.
They can distinguish between homozygous susceptible (SS), homozygous resistant (RR), and heterozygous (RS) individuals in a population.
This early detection is essential for executing proactive resistance management actions before resistance becomes widespread. Thus, Statement I is correct.
- Statement II: This statement asserts that using genetically engineered (GE) crops does not delay the development of resistance.
In transgenic insect-resistant crops (like Bt cotton), the toxin is expressed continuously throughout the growing season, imposing a strong, continuous selection pressure on the pest population.
This selection pressure actually accelerates, rather than delays, the development of resistance unless mitigation strategies, such as the high-dose refuge strategy, are strictly enforced.
Therefore, the use of GE crops itself does not delay resistance; rather, it necessitates active management to avoid rapid resistance development. Thus, Statement II is incorrect.
Consequently, Statement I is correct and Statement II is incorrect.

Step 3: Final Answer
The correct option is (C).