Question

A long day plant flowers only if exposed to a light period of

• A. more than its critical day length.
• B. less than its critical day length.
• C. equal to its critical day length.
• D. slightly less than its critical day length.

Answer 1

The correct option is A more than its critical day length.

A long day plant can flower only when it is exposed to a day length more than its critical day length. Examples of long day plants are spinach, radish and wheat.