Nastic movement is a plant component reaction that is unaffected by the direction of the external stimuli.
Nastic movements are movements found in plants while responding to environmental stimuli; however, unlike tropic movements, the course of the reaction is not reliant on the direction of the stimulus.
Light, heat, touch, and other stimuli are examples of stimuli.
This movement occurs in the plant's flat organs, such as leaves and flower petals.
The nastic motions are a few of the most noticeable plant movements.
This includes the carnivorous Venus Flytrap leaf closing as it catches its prey and the crimping of mimosa leaves when disturbed.
Types of nastic movements: Plants exhibit five forms of nastic movements:
Seismonastic movement:
This kind of movement is induced by mechanical stimulation, observed in stigmas, stamens, and leaves.
For instance, the movement of Mimosa pudica leaflets reveals seismonastic movement.
Photonastic movement:
It is the movement caused by light.
For example, Cestrum nocturnum flowers open at night and close as the day breaks.
Thermonastic movement:
It is caused by temperature changes.
For example, the leaves of Rhododendrons curl up and close during low temperatures.
Nyctinastic movement:
This movement is caused by changes in light and temperature; also known as a sleeping movement.
Some plants, including Enterobium, clover, and Oxalis, grow their leaves roughly horizontally during the day, but as evening approaches, they start to droop and close.
Thigmonastic movement:
This movement is a reaction to an object's touch.
The coiling of tendrils or twiners as they come into contact with things for support is an illustration of thigmotropism.