Plant Growth Regulators with special reference to Agriculture and Horticulture

Sol –

Plant growth regulators (PGRs) are small, simple molecules with diverse chemical compositions that regulate various aspects of plant growth and development. These regulators can be broadly divided into two groups based on their functions within a living plant body

Growth Promoters

Growth Inhibitors

Stimulate growth-promoting activities such as cell division, enlargement, pattern formation, and flowering.

Regulate responses to wounds and stresses, and inhibit growth activities such as dormancy and abscission.

Auxins 

  • Promote cell elongation, root initiation, and apical dominance
  • Natural -Indole-3-acetic acid(IAA), indole butyric acid (IBA)
  • Synthetic – NAA (naphthalene acetic acid) and 2, 4-D (2,4-dichlorophenoxyacetic)

Gibberellins 

  • Stem elongation, seed germination, and flowering in plants.
  • e.g., Gibberellic acid pGA3) – 

Cytokinins 

  • regulate cell division, lateral shoot initiation, and delay senescence
  • e.g., Zeatin

Abscisic Acid (ABA) 

  • Regulate seed dormancy, stomatal closure, and responses to environmental stresses such as drought and salinity.
  • Example: Abscisic acid (ABA) is naturally synthesized in plants in response to stress
  • Ethylene 
  • A gaseous hormone that regulates fruit ripening, leaf abscission, and senescence 
  • Used both as a promoter and an inhibitor 
  • e.g., Ethephon

Leave a Comment

Your email address will not be published. Required fields are marked *

error: Content is protected !!
Scroll to Top
Telegram WhatsApp Chat