Question

The PGRs which play an important role in plant responses to wound and stresses of biotic and abiotic origin and also involved in various growth inhibiting activities such as dormancy and abscission is/are

Answer 1

Plant growth regulators are organic compounds responsible for signalling, control and regulation of plant growth. These are also known as phytohormones or plant hormones.
Plant growth regulators can be divided into two types-

• Growth promoting regulators
• Growth inhibiting regulators

Regulators which inhibit plant growth by initiating growth inhibiting activities, such as plant growth, seed germination etc. as well as promoting seed dormancy, senescence and abscission are known as growth inhibiting regulators.
Ethylene and abscisic acid are two phytohormones having growth inhibiting effects.
Abscisic acid is also involved in increasing stress tolerance of plants during unfavourable environmental conditions.