Question

Self-incompatibility is observed in ______.

• A. Orchids
• B. Callistemon
• C. Salvia
• D. Cestrum

Hint:

Self-incompatibility prevents self-fertilization and promotes cross-pollination to increase genetic variation.

Answer 1

The Correct Option is A

Step 1: Understanding self-incompatibility.
Self-incompatibility is a genetic mechanism present in some flowering plants that prevents self-pollination. This mechanism ensures cross-pollination and helps in maintaining genetic diversity within the species.
Step 2: Analyzing the options.
(A) Orchids: Correct. Orchids commonly show self-incompatibility mechanisms that prevent self-fertilization.
(B) Callistemon: Incorrect. Callistemon mainly depends on pollinators and does not show true genetic self-incompatibility.
(C) Salvia: Incorrect. Salvia shows a special pollination mechanism but not self-incompatibility.
(D) Cestrum: Incorrect. Cestrum does not exhibit self-incompatibility.
Step 3: Conclusion.
The correct answer is (A) Orchids because they exhibit a genetic self-incompatibility mechanism.