Nicotiana tabacum, a Short-Day plant, when exposed to more than critical of light fails to flower. Explain.
Nicotiana tabacum is a short-day plant, and these plants require much less exposure to light than the required amount in normal plants. They demand a continuous critical dark period, which if interrupted, can affect the flowering of the plant. These plants require a photoperiod less than the general required one and played a key role in flowering. This is due to the fact that flowering is regulated by a hormone which is present in the leaves and requires the dark photoperiod to migrate to the required places in the shoot apices.