Question

If a tree flowers thrice in a year in October, January and July in northern India, the plant is

• A. Photo- and thermo-sensitive
• B. Photo- and thermo-insensitive
• C. Photosensitive but thermo-insensitive
• D. Thermosensitive but photo-insensitive

Answer 1

The correct option is D Thermosensitive but photo-insensitive

Flowering in plant is dependent on two factors, photoperiodism and vernalization. Vernalization is flowering of plants on exposure to prolonged period of low temperature. Photoperiodism is flowering in plants in response to change in day length. In the given example, flowering is taking place during any part of the year. Hence, the plant is not sensitive to light period.

Thus, the correct answer is option D.