Correct option is A
Correct Answer: (a)
Explanation: Short-day plants flower when they experience a sufficiently long, uninterrupted dark period. In option 1, the light phase is followed by a continuous and extended dark phase without any light interruption. This uninterrupted night allows the appropriate photoperiodic signaling required for floral induction. Hence, treatment 1 promotes flowering in short-day plants.
Information Booster
· Photoperiodism depends primarily on the length of the dark period, not the light period.
· Short-day plants require a critical minimum night length to flower.
· Light interruptions during the night (night breaks) inhibit flowering in short-day plants.
· Phytochrome interconversion during darkness is crucial for floral induction.
· Continuous darkness permits conversion of active phytochrome to its inactive form, favoring flowering.
Additional Knowledge
In treatments where the dark period is short or interrupted by light pulses, the photoperiodic requirement of short-day plants is not met. Even brief light exposure during the night resets the phytochrome system and suppresses flowering. Therefore, treatments showing night breaks or insufficient dark duration fail to induce flowering, unlike the uninterrupted long dark period seen in option 1.
