ABSTRACT
Plant hormones are naturally occurring chemicals formed inside plants. They play vital role in various biological activities in plant. These plant regulators are active at very low concentration. They are also used in as pesticides and promote growth of plants. They are called growth regulators 282as they help in increase of cell size, volume, and weight of any part of plant’s body by cell division and cell enlargement, and development of irreversible change in state. In this chapter, we highlight nature, activity, structure, and the important biological roles of plant hormones. These regulators are now-a-days widely used for commercial uses in nurseries, gardens, and crop fields for better yield.
