Question

Given below are two statements.
Statement I - Gibberellins promote flowering in long day plants.
Statement II - ABA inhibits flowering in long day plants but stimulates flowering in short day plants.
In the light of above statements, choose the correct option 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:

Hormone rule: Gibberellins = growth + flowering; ABA = inhibition + dormancy.

Answer 1

The Correct Option is C

Concept:
Plant growth regulators (PGRs) play important roles in flowering. Among them, gibberellins and abscisic acid (ABA) have contrasting effects.

Step 1: Analyze Statement I. Gibberellins are known to promote flowering in long day plants (LDPs) and can even substitute for long-day conditions in some cases. \[ \text{Gibberellins} \rightarrow \text{Promote flowering in LDPs} \] Thus, Statement I is correct.

Step 2: Analyze Statement II. ABA is generally a growth-inhibiting hormone. It:
• Inhibits flowering in most plants
• Promotes dormancy and stress responses There is no standard concept that ABA stimulates flowering in short day plants. Thus, Statement II is incorrect.

Step 3: Conclusion. \[ \text{Statement I is correct, Statement II is incorrect} \]