The abscission layer is covered by a leaf scar which is composed of

Plant movement in response to diffuse stimulus of light is

$A$ clinostat is an instrument used in experiments related to:

Choose the incorrect pair.

The movement in the "Touch-me-not" plant $(Mimosa pudica)$ in response to touch is known as:

List five main groups of natural plant growth regulators. Write a note on discovery,physiological functions and agricultural/horticultural applications of any one of them.