Question

The PGRs can be broadly divided into two groups based on their functions in living plant body. One group of PGRs are involved in growth promoting activities, such as cell division, cell enlargement, pattern formation, tropic growth, flowering, fruiting and seed formation. These are also called

Answer 1

Plant growth regulators are the 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 promote plant growth by growth promoting activities, such as cell division and enlargement, pattern formation, tropic growth, flowering, fruiting as well as seed formation are known as growth promoting regulators.
Different regulators having growth promoting effects are auxin, cytokinin, gibberellins and ethylene.