Difference Between Auxin and Gibberellin (original) (raw)
Last Updated : 23 Jul, 2025
The **difference between auxin and gibberellin lies in the plant parts they target for growth. Both Auxin and Gibberellins are **plant hormones. Every cell in a plant has the potential to make plant hormones. For a plant to germinate, auxin and gibberellins are both required.
Auxin helps promote root growth and gibberellin promotes shoot growth. Both auxin and gibberellins are similar in some manner as they are both involved in the development of plants through cell expansion. In this article, we will read about the differences between auxin and gibberellin along with some similarities.
Table of Content
- What is Auxin?
- What is Gibberellin?
- Difference Between Auxin and Gibberellin
- Similarities Auxins and Gibberellins
- Conclusion: Difference Between Auxin and Gibberellin
- Difference Between Related Links
- FAQs on Auxin and Gibberellin
What is Auxin?
The Greek verb auxin, meaning "to grow," is where the name "auxin" comes from. In phototropism and gravitropism, auxins are the primary hormones responsible for cell elongation. Additionally, they control how meristems differentiate into vascular tissue and support the growth and arrangement of leaves. **Indole acetic acid (IAA) is the only naturally occurring auxin that has physiological activity, but numerous synthesized auxins are utilized as herbicides.
Auxins generated in the apical meristem cause apical dominance, which inhibits the development of lateral buds. IAA is a rooting hormone that is used to encourage the establishment of accidental roots on cuttings and severed leaves. In greenhouse tomato plants, synthetic auxins encourage healthy fruit development. Other plant responses under the direct or indirect regulation of auxins include flowering, fruit setting ripening, and preventing abscission (leaf falling).
**Also Read: Tropic Movements In Plants
What is Gibberellin?
Gibberellins (GAs) are a family of roughly **125 closely related plant hormones that promote fruit and blossom ripening, shoot elongation, and seed germination. Young leaves, seed embryos, and the apical meristems of roots and stems all produce GAs. GA antagonists are sometimes used on trees beneath power lines in metropolitan areas to restrict growth and lessen the need for pruning.
The seeds of plants that require exposure to cold or light to germinate are released from their state of dormancy, which is characterized by limited growth and development. Gender expression, the growth of seedless fruit, and the postponement of senescence in leaves and fruit are additional effects of GAs. GA is frequently applied to maturing grapes to encourage increased fruit size and looser bunches (longer stems), which lowers the likelihood of mildew infection.
**Also Read: Gibberellins – Location, Structure, Functions and Uses
Difference Between Auxin and Gibberellin
The following table highlights the differences between Auxin and Gibberellin:
| Characteristic | Auxin | Gibberellin |
|---|---|---|
| **Structure | Auxin has an unsaturated structure and either a single or double side chain. | The structure of gibberellin is a saturated, side-chain-free tetracyclic gibbane. |
| **Discovered in | Higher plants. | Both higher plants and in fungi. |
| **Root Growth | Inhibits root growth at normal concentrations. | Has no effect on root growth. |
| **Shoot Growth | Promotes the expansion of shoot segments. | Promotes the healthy shoot's growth. |
| **Leaf Growth | Has little effect on the development of leaves. | Increases the rate of leaf growth |
| **Seed and Bud Dormancy | Does not break dormancy in seeds and buds | Gibberellin is essential for seed germination because it induces bud and seed dormancy. |
| **Callus Growth | It is crucial for the development of callus. | It has no effect on the development of the callus. |
| **Transport | Basipetal transport is used. | Both basipetal and acropetal transport is used |
| **Hormonal Effects | It has a hormonally feminizing impact. | It has a hormonally masculine impact. |
| **Functions | Axial elongationCell divisionDifferentiationCellular expansionLateral expansion | Stem elongation Seed germinationFruit senescence Breaks DormancyEnzyme Induction |
Similarities Auxins and Gibberellins
The following similarities are seen in Auxin and Gibberlins:
- Both Auxin and Gibberellin help in promoting plant growth by elongating various parts of the plant.
- Cell Expansion is carried out both by both Auxin and Gibberellin.
- Both these hormones are often seen interacting synergistically to each other.
- Both Auxin and Gibberellin are involved in the process of seed germination.
- Auxin is directly involved in phototropism and geotropism. Gibberellin supports the tropism through cell elongation.
Conclusion - Difference Between Auxin and Gibberellin
Auxin and Gibberelin are both plant hormones that help in plant's growth. Auxin helps in axial elongation, cell division, and cell differentiation. On the other hand, gibberellin is involved in stem elongation, seed germination, and dormancy. During seed germination, auxin helps in root growth and Gibberelin assists in stem growth.
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