Photoperiodism was first observed in

The red absorbing form of phytochrome gets converted to the far-red absorbing form after getting irradiated at

$A$ pigment responsible for light sensitivity in plants is

Some varieties of wheat are known as spring wheat while others are called winter wheat. The former variety is sown and planted in spring and is harvested by the end of the same season. However,winter varieties,if planted in spring,fail to flower or produce mature grains within a span of a flowering season. Explain,why?

Analogy type questions:
$(1)$ Coconut milk : Zeatin : : $ABA$ : ...............
$(2)$ Phenolic acid : Seed dormancy : : Cold treatment : ...............

If a tree flowers thrice in a year $(October, January, \text{and } July)$ in Northern India, it is said to be