Question

Phytohormone which induces triple response is
A. IAA
B. ABA
C. GA3
D. C2H4

Answer 1

Hint: Plant hormones are responsible for the plant growth and plant development, pathogen defense, stress tolerance, etc.

Complete Answer:
Phytohormones: Phytohormones are the signal molecules that occur in extremely low concentrations.
- They are the small organic molecules.
- There are many phytohormones found, for example – gibberellic acid, ethylene, indole acetic acid, etc.
- Phytohormone which induces triple response is Ethylene.

Ethylene as plant hormone: Ethylene is a first identified plant hormone.
- Ethylene is an unsaturated carbon compound which naturally acts as a plant hormone.
- It is a multifunctional hormone that regulates both growth and senescence.

Functions of Ethylene:
- Stimulating the fruit ripening.
- Increases the speed of leaf and flower senescence.
- Induces flowering.
- Inhibits stem growth.
- Induces root growth in order to absorb more and more water.
- Helps in determining the sex of a flower.
- Helps in root initiation and pollination.

So, from the above discussion it is clear that the D is the right option for this question.

Note: Ethylene is an organic compound which is also used in manufacturing numerous products such as plastics, paints, rubber, toys, detergents, etc. It is also used in agricultural work for obtaining more yield.