Plant Growth Regulator 
A substance which regulates, primarily by reducing or restricting, the activity of plant hormones. The main groups of PGRs are abscisic acid, auxin, cytokinin, ethylene and gibberellin.
Plant Growth Regulator
A substance which regulates, primarily by reducing or restricting, the activity of plant hormones. The main groups of PGRs are abscisic acid, auxin, cytokinin, ethylene and gibberellin.