Question

Name a few plant growth promoters.

Answer 1

Plant growth promoters: Plant growth promoters are said to be those that promote cell division, or cytokinesis, in plant roots & shoots.

1. Auxins are one of most important plant hormones. The chief naturally occurring auxin is an indole-3 acetic acid – IAA and other related compounds.
   1. Functions of the Auxins:
      1. Facilitate flowering in the plants.
      2. Used in process of plant propagation.
      3. Used by gardeners to keep the lawns free from weeds.
      4. Involved in initiation of roots in stem cuttings.
      5. Prevention of dropping of the leaves and fruits at early stages.
      6. Regulate xylem differentiation & assists in cell division.
2. Gibberellins are the other plant growth promoter.
   1. Functions of Gibberellins:
      1. Delay senescence in the fruits.
      2. Involved in leaf expansion.
      3. Break bud & seed dormancy.
      4. Promote bolting in the cabbages and beet.
      5. Facilitate elongation of fruits like apples and enhance their shape.
3. Cytokinins: They are produced in regions where cell division generally occurs; mostly in the roots and shoots.
   1. Functions of Cytokinins:
      1. Break bud & seed dormancy.
      2. Promotes growth of lateral bud.
      3. Promotes cell division & apical dominance.
      4. They are also used to keep flowers fresh for a longer time.
4. Ethylene:
   1. Ethylene is a group of plant growth regulators that are widely used for the purpose of ripening fruits and for the production of more flowers and fruits.
   2. The ethylene found in plants acts as a growth regulator, even in trace amounts throughout the entire plant life by regulating and stimulating the opening of flowers, fruit ripening and shedding of leaves.
5. Abscisic acid:
   1. Abscisic acid is a growth inhibitor hormone in plants.
   2. It acts as an antagonist to gibberellic acid.
   3. It is also referred to as a stress hormone, as it increases tolerance during stress conditions.