The various plant hormones are Auxin, Gibberellin, Cytokinin, and Abscisic acid.

Their physiological effects on plant growth are as follows:

Auxins: Cell elongation, cell division, root formation, apical dominance, inhibition of abscission and fruit growth.

Gibberellins: Growth in stem and leaves, higher fruit yield and over coming dormancy.

Cytokines: Promotes cell division, differentiation, prevention of senescence and overcoming apical dominance.

Absciscic acid: Induces dormancy, senescence, abscission, checking excessive activity of growth promoting hormone and closure of stomata under water stress.