Plant hormones and growth regulators are chemicals that affect flowering; aging; root growth; distortion and killing of leaves, stems, and other parts; prevention or promotion of stem elongation; color enhancement of fruit; prevention of leafing and/or leaf fall; and many other conditions. Very small concentrations of these substances produce major growth changes.

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Palnt Grorth Regulators are responsible for the growth and development of the plants..

What is a hormone?
As plants grow their genotype is expressed in the phenotype which is modified by the environmental conditions that they experience. Somehow the rates of growth and differentiation of cells in different parts of the plant are coordinated in response to these inputs.

Suggested Books for this Topic:

Bhan (1998), Tissue Culture Mittal Publications, New Delhi

Gupta P.K, Elements of Biotechnology, Rastogi & Co.

Dr. U. Satynarayana, Biotechnology