Ques. 1AIPMT 2012 (Mains)
Through their effects on plant growth regulators, what do the temperature and light control in the plants?
- Apical dominance
- Flowering
- Closure of stomata
- Fruit elongation
Answer
(2) Flowering
Solution
Light (photoperiod) and temperature (vernalisation) act through plant growth regulators (e.g. florigen, gibberellins) to control the onset of flowering.
⇒ Photoperiodism: flowering depends on the relative length of day and night.
⇒ Vernalisation: flowering is promoted by exposure to low temperature.
Answer: (2)