Question

Nicotiana tabacum, a Short Day Plant, when exposed to more than critical period of light fails to flower. Explain.

Answer 1

Plants that need to be exposed to light for a shorter length of time than the crucial light period are known as short-day plants. Only when the photoperiod is below the critical period, i.e. when there is a continuous extended dark period, does this plant blossom. These plants do not develop blooms when exposed to a photoperiod that is longer than the crucial period. In plants, a hormone causes flowering. In response to the needed photoperiod, the hormone is found in leaves and migrates to the shoot apices.