Question

When a plant experiences no stress, which of the following growth regulators displays a decline in production?

• A. Ethylene
• B. ABA
• C. IAA
• D. GA

Answer 1

Answer:

B. ABA

• Plant growth regulators are the chemical substances which govern all the factors of development and growth within plants.

• Some other names used to refer to it are phytohormones and plant growth hormones.

• Auxins, Gibberellins, and Cytokinins are grouped into Plant growth promoters while Abscisic acid and Ethylene are grouped into Plant growth inhibitors.

  Abscisic acid

• It is a growth inhibitor which serves as an antagonist to Gibberellic acid.

• It is also known as the stress hormone as it helps by increasing the plant-tolerance to various types of stress.

  Functions of Abscisic acid

• Stimulates closing of stomata in the epidermis.

• Helps in the maturation and development of seeds.

• Inhibits plant metabolism and seed germination.

• It is involved in regulating abscission and dormancy.

• It is widely used as a spraying agent on trees to regulate dropping of fruits.

• Induces seed-dormancy and aids in withstanding desiccation and various undesired growth factors.