Consider the following statements: Which of the following plant hormones helps in promoting growth in plants? 1. Auxins 2. Gibberellins 3. Cytokinins 4. Abscisic Acid How many of the statements given above are correct?

• Plant hormones, also known as phytohormones, play a crucial role in regulating various aspects of plant growth and development.

The key growth-promoting plant hormones are

Auxins

• Auxins are primarily involved in cell elongation, root initiation, and differentiation.
• They play a crucial role in apical dominance, where the main central stem of the plant is dominant over other side stems.

Gibberellins

• Gibberellins are essential for various growth processes, including seed germination, stem elongation, and flowering.
• They help in breaking dormancy and initiating seed germination.

Cytokinins

• Cytokinins promote cell division (cytokinesis) and differentiation, particularly in the roots and shoots.
• They work in conjunction with auxins to regulate growth and development.

Brassinosteroids

• Brassinosteroids are involved in cell expansion, elongation, and overall plant growth.
• They are also crucial in stress responses and development.

Ethylene (Growth-promoting in some contexts)

• Although ethylene is generally known for its role in fruit ripening and senescence, it also promotes growth in certain conditions, such as the triple response in seedlings, where it inhibits stem elongation, promotes stem thickening, and causes horizontal growth.

Additional information

• Unlike other plant hormones that primarily promote growth, abscisic acid is often associated with inhibitory effects on plant growth and development.
• ABA plays a significant role in inducing and maintaining seed dormancy, preventing seeds from germinating under unfavourable environmental conditions.