The hormonal substance which migrates from leaves to shoot apices to induce flowering is

Differentiate between Photoperiodism and Vernalization.

There are many plants that do not show any correlation between exposure to light duration and the induction of flowering. Such plants are called $..........$.

Give scientific reasons: It is appropriate to call a short-day plant a long-night plant.

Classify the following plants into Long Day Plants $(LDP)$, Short Day Plants $(SDP)$, and Day Neutral Plants $(DNP)$: Xanthium, Henbane $(Hyoscyamus \text{ } niger)$, Spinach, Rice, Strawberry, Bryophyllum, Sunflower, Tomato, Maize.

In which plant was the importance of day length for flowering first observed?