It is a kind of plant organ that is used for anchoring and supporting the vining system. It can be a modified structure of leaves, leaflets, leaf tips, or leaf stipules. They may also be derived from modified stem branches like in grapes. They are thin, thread-like growths present on the stem or leaves of climbing plants. Based on growth tendril are of two types they are: stem tendril and leaf tendril. And their growth is mainly towards the support with which they can attach themself for the support and this phenomenon is known as thigmotropism.
Function of Tendril
Some of the common function of tendril are discussed below:
They are known to be modified portions of leaf, stem or petiole.
Their main function is to provide support to the plant as it climbs up a structure. By doing so they allow a plant to find a more suitable area to grow due to more light.
When stems are modified into tendril they help plants to climb.
The Positions of tendril are different in different plants like in leaf, stem or even branches in few plants.
When stems are modified into threadlike leafless structure then they are known as stem tendril. Their major role is for climbing purposes, they don't necessarily contain a branch.
Further Stem Tendril Are Classified Into Different Types, They Are
Axillary: E.g., Passiflora
Extra-Axillary: E.g., Luffa
Apical Bud: E.g., Grapevine
Floral Bud: E.g., Antigonon
What is Thigmotropism?
It is a kind of curvature movement shown by a plant in response to a unilateral touch stimulus and can be observed in many climbers. In tendril climbers, the tendrils first show mutation, and as soon as their apices touch support, they move thigmotropic ally to turn around it.
Some of the common examples of tendril-producing plants are the grape, members of the squash or melon family (Cucurbitaceae), the sweet pea (Lathyrus odoratus), and the passion flowers (Passiflora species).
Explain the Role of Auxin in the Growth of Tendril
It is a kind of growth hormone which is generally synthesized at the shoot tip. It enhances the growth of cells so that plants can increase their length. As soon as the tendril comes in contact with any support system, auxin stimulates the cell to grow faster on the opposite side that’s why the tendril forms a coil around the support.
Some of the Common Examples of Auxin Based on Their Synthesis Are
Naturally occurring auxins: Indole acetic acid, indole ethanol, indole acetaldehyde.
Synthetic auxins: Naphthalene acetic acid, indole butyric acid, 2,4-dichlorophenoxyacetic acid.