The site of perception of light/dark duration in plants is:
1. Root apex
2. Shoot apex
3. Flower
4. Leaves
One set of a plant was grown at 12 hours a day and 12 hours night period cycles and it flowered while in the other set, night phase was interrupted by a flash of light and it did not produce a flower. Under which one of the following categories will you place this plant?
1. Darkness neutral
2. Day neutral
3. Short day
4. Long day
Flowering will take place in a short day plant only when:
1. days are shorter than nights.
2. days are shorter than a certain critical value.
3. nights are shorter than a certain critical value.
4. nights are longer than a certain critical value.
I: | The process, by which exposure to cold renders plants competent to flower is called vernalization. |
II: | Even after vernalization, the plant must be subjected to a suitable photoperiod, usually long days. |
III: | Like photoperiod, vernalization is also perceived in leaves. |
IV: | In most biennial long day plants that form rosettes, gibberellins treatment can substitute for the cold requirement. |
1. | Only I, II and III | 2. | Only I, II and IV |
3. | Only II, III and IV | 4. | I, II, III and IV |