What is Auxin?
Auxin is plant hormone which is synthesized at the tip of the shoot. It helps the cell grow longer. When a tendril comes in contact with a support, auxin stimulates faster growth of the cells on the opposite side that’s why the tendril forms a coil around the support.
What are the effects of Auxins?
There are four key effects of auxins on plant growth and they are:
(a) Shoot elongation gets stimulated: The length of plant is dependent on the gibberlins and these get influenced by the auxins.
(b) Orientation of seedling: It was found that seedlings have a tendency to bend towards light. But the presence of auxins influence the cells in the plants. Auxins are affected by the gravity resulting in their accumulation at the bottom and we know that cells grow more where there is high concentration of auxins.
(c) Branching of root: Roots can be obtained at the cuts by applying auxin.
(d) Promoting fruit development: Presence of auxins in the flowers promotes maturation of ovary and further into a fully developed fruit.
Types of Auxins
Auxins can be either naturally occuring or obtained synthetically.
- Naturally occuring auxins: Indole acetic acid, indole ethanol, indole acetaldehyde.
- Synthetic auxins: Napthalene acetic aicd, indole butyric acid, 2,4-dichorophenoxyacetic acid.