Question

While studying flowering behaviour in ________ and ________ plant, Garner and Allard discovered photoperiodism.

• A. rice, wheat
• B. tobacco, soyabean
• C. tomato, soyabean
• D. wheat, tobacco

Hint:

Photoperiodism discovery: Garner & Allard $\rightarrow$ Tobacco + Soybean

Answer 1

The Correct Option is B

Concept: Photoperiodism is the response of plants to the relative length of day and night, especially in relation to flowering.
• Discovered by Garner and Allard (1920s)
• Based on experiments on specific plants showing flowering response to light duration

Step 1: Understand discovery.
Garner and Allard studied how light duration affects flowering.

Step 2: Identify plants used.
They conducted experiments on:
• Tobacco (Maryland Mammoth variety)
• Soybean

Step 3: Analyze options.
• (A) Rice, wheat: Incorrect
• (B) Tobacco, soybean: Correct
• (C) Tomato, soybean: Incorrect
• (D) Wheat, tobacco: Incorrect

Step 4: Conclusion.
Thus, photoperiodism was discovered using tobacco and soybean. Final Answer: Option (B)