Apical Dominance

Biology

PRODUCTION OF AUXINS AND THEIR EFFECTS ON PLANT GROWTH

PRODUCTION OF AUXINS AND THEIR EFFECTS ON PLANT GROWTH.

Auxins are produced by plant apices, i.e. root apex and shoot apex.
They bring about cell elongation resulting in growth.
They are diffusible substances which effect growth when in very small amounts.
Roots require lower concentrations than shoots.
The effect of auxins on the growth of roots and shoots has already been discussed.
Auxins also exert other effects on plant growth and development.
There are various other chemical substances which have been shown to influence plant growth and development.

Biology

ROLE OF GROWTH & HORMONES IN PLANTS

ROLE OF GROWTH & HORMONES IN PLANTS.
Plant hormones are chemicals produced in very small amounts within the plant body, and play a very important part in regulating plant growth and development. Most growth hormones are produced at the tip of a shoot and transported downwards to the root. The root tip produces very small quantities of the hormones.
There are many different types of plant hormones and one well-known group is the auxins. Indoie acetic acid (IAA) is one best known auxin. Auxins are produced at the shoot and root tips.