In 1926 E Kurosawa discovered that the reason seedlings where growing so tall and toppling over is because of the disease caused by a fungus of the genus Giberella. Four years later Japanese scientist concluded that the fungus produced hyperelongation of stems by secreting a chemical called gibberellins. Over the last thirty years many different scientist identify over seventy types of gibberellins, most of which occurred naturally in plants. Some types are much more active then others. Growth regulators are normally overdosed in plants of lower concentrations.
Gibberellins have many different effects on plants.
Gibberellins production occurs mainly in the roots and young leaves. Little growth actually occurs in the root but mainly in the leaves and stems. Even though there is little effect on the root growth, the gibberellins stimulate growth in the stems and leaves. Inside the stems the gibberellins stimulate cell division and cell elongation. Both auxin and gibberellins have to act together in a growing stem.