Question

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A): Gynogenic haploids have been developed by determining the optimum stage of male gametophytic development.
Reason (R): Late uninculeate to trinucleate stage of megaspore development is preferred for the production of gynogenic haploids.
In the light of the above statements, choose the most appropriate answer 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:

Gynogenesis = Female (Megaspore/Ovary).
Androgenesis = Male (Microspore/Anther).
Don't let the technical terms for "Male" and "Female" confuse you!

Answer 1

The Correct Option is D

Concept: Gynogenesis is the production of haploids from the female gametophyte (megaspore/egg cell). The success of this process depends on the developmental stage of the female tissues.

Step 1: Evaluating the Assertion (The Error).
Assertion (A) is incorrect. Gynogenic haploids are developed from female gametophytic tissues. The "optimum stage of male gametophytic development" would be relevant for androgenesis (anther/pollen culture), not gynogenesis.

Step 2: Evaluating the Reason.
Reason (R) is correct. For the successful induction of haploid embryos from female tissues, the megaspore or embryo sac needs to be at a specific maturity level, generally ranging from the late uninucleate stage up to the mature trinucleate/organized embryo sac stage.

Step 3: Conclusion.
Because the Assertion misidentifies the gametophyte source for gynogenesis while the Reason correctly identifies the developmental stages of the female megaspore, option (4) is the correct choice.