Question

Which does not take place in short day plants?

• A. An interrupted critical dark period
• B. Critical period is interrupted by light
• C. Dark period is interrupted by red light followed by far-red light
• D. Critical period is not interrupted by white or red light

Answer 1

The correct option is B Critical period is interrupted by light

Short day plants are those plants that begin flowering when the days are shorter than their critical day length. They require long period of darkness and short period of light to flower. In this, the critical period is dark period which must be continuous and uninterrupted. If this is interrupted by brief period of red light, it will not flower. However, this effect can be reversed by exposure of far-red light immediately after red light.

Thus, the correct answer is option B.