Question

Which one of the following crops is most sensitive to photoperiod?

• A. Wheat
• B. Rice
• C. Maize
• D. Barley

Hint:

Rice is a short-day crop and is commonly used as an example of photoperiod-sensitive plants.

Answer 1

The Correct Option is B

Step 1: Understanding photoperiod sensitivity.
Photoperiod sensitivity refers to a plant’s response to the length of day and night, especially in relation to flowering. Some crops require specific day lengths to initiate flowering.
Step 2: Classification of crops based on photoperiod.
Crops can be classified as short-day, long-day, or day-neutral plants. Short-day plants flower when the day length is shorter than a critical value.
Step 3: Identifying the photoperiod-sensitive crop.
Rice is a classic short-day plant and shows strong sensitivity to day length. Its flowering is highly influenced by photoperiod, especially in traditional varieties.
Step 4: Analyzing the options.
(A) Wheat: Wheat is a long-day plant but is relatively less sensitive compared to rice.
(B) Rice: Correct — Rice is highly sensitive to photoperiod and flowering depends strongly on day length.
(C) Maize: Maize is mostly day-neutral or weakly photoperiod-sensitive.
(D) Barley: Barley is a long-day plant but less sensitive than rice.
Step 5: Conclusion.
Among the given crops, rice is the most sensitive to photoperiod.