Question

Given below are two statements, one is labelled as Assertion (A) and other is labelled as Reason (R).
Assertion (A) : Clonal selection followed by vegetative propagation is a major strategy for improvement of perennial crops.
Reason (R) : A large genetic advance can be made in a single step without the multiple generation of seed propagation required of seed propagated cultivars.
In light of the above statements, choose the most appropriate answers from the options given below.

• A. Both (A) and (R) are correct and (R) is the correct explanation of (A)
• B. Both (A) and (R) are correct but (R) is not the correct explanation of (A)
• C. (A) is correct but (R) is not correct
• D. (A) is not correct but (R) is correct

Hint:

Vegetative propagation "freezes" the heterozygous genotype.
This allows breeders to immediately commercialize outstanding individual trees without worrying about genetic segregation.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
This question focuses on breeding strategies for perennial horticultural crops (such as fruit trees like mango, citrus, and apple).
These crops are highly heterozygous and have long juvenile phases, making traditional seed-based breeding slow and challenging.

Step 2: Detailed Explanation:
Let us analyze the assertion and reason:
Assertion (A): "Clonal selection followed by vegetative propagation is a major strategy for improvement of perennial crops."
This statement is correct.
Perennial fruit crops are highly heterozygous.
When propagated by seed, their offspring show high genetic segregation, losing the desirable traits of the parent plant.
To overcome this, breeders select a single superior tree (clonal selection) and propagate it vegetatively (using grafting, budding, or cuttings) to maintain its exact genetic makeup.
Reason (R): "A large genetic advance can be made in a single step without the multiple generation of seed propagation required of seed propagated cultivars."
This statement is correct.
Because perennial crops can be propagated vegetatively, any superior genotype found in a seedling population can be cloned immediately.
This allows breeders to capture and lock in a massive genetic improvement in a single step.
This avoids the multiple generations of backcrossing and selfing required to stabilize traits in seed-propagated annual crops.
This immediate stabilization is the primary reason why clonal selection is the dominant breeding strategy for these crops.
Thus, (R) directly explains (A).

Step 3: Final Answer:
Both (A) and (R) are correct, and (R) is the correct explanation of (A).
This corresponds to Option (A).