PREVIOUSLY ASKED IN:
WBPSC Miscellaneous Preliminary 2019
Answer
Ethylene
Explanation
Ethylene is widely used for the ripening of fruits. It is a naturally occurring plant hormone that exists in a gaseous state. Ethylene regulates the ripening process by accelerating it, changing the color of the fruit, and softening it. Commercially, ethylene gas or chemicals like ethephon (which release ethylene slowly) are used for artificial ripening of fruits like bananas and mangoes.
Key Points
- > Ethylene (C2H4) is the only plant hormone that exists as a gas at room temperature.
- > Calcium carbide was formerly used for artificial fruit ripening but is now banned in many places due to its toxic health effects.
- > Auxin is a plant hormone that promotes cell elongation and stem growth.
- > Cytokinin is primarily responsible for promoting cell division in plants.
- > Gibberellins help in breaking seed dormancy and promoting stem elongation.
Additional Information
Major Plant Hormones & Functions
| Hormone | Primary Function | Nature |
|---|---|---|
| Auxin | Cell elongation, apical dominance | Growth Promoter |
| Gibberellin | Seed germination, internode elongation | Growth Promoter |
| Cytokinin | Cell division, delays senescence | Growth Promoter |
| Ethylene | Fruit ripening | Gaseous Hormone |
| Abscisic Acid (ABA) | Stress hormone, induces dormancy | Growth Inhibitor |
Memory Tips
- Ethylene: "E" for Eating ripe fruits (Fruit Ripening).
- Auxin: "A" for Apical growth.