Gibberellins are substances which promote shoot elongation for certain mutants of Zea mays, certain varieties of Phaseolus or Pisum or certain varieties of plants that have rosette habit of growth.
In 1926 Kurosawa, a plant pathologist working on Formosa found that cell free filterate of the medium in which the fungus Gibberella fujikuroi (Fusarium moniliforme) had been growing had unusual physiological properties. This fungus is responsible for the “bakanae” (foolish seedling) disease of rice. Most characteristic symptoms of the disease were abnormal growth of stem, leaves, thin plants with long internodes, flowers early or die before flowering and fruiting.
In 1939, Yabuta and Hayashi and coworkers working in Tokyo isolated an active substance from the fungus and called it Gibberellin A. This first gibberellin preparation was probably a mixture of several gibberellins. The first gibberellin to be obtained was Gibberellin A 3. Now 52 gibberellins have been identified from different groups of plants.