ABSTRACT
Gibberellin (GA) is one group of plant hormones, which has a chemical structure of gibberellane skeleton (Fig. 1). GA is involved in almost all phases of plant growth and development. GA promotes germination, elongation growth of roots and stems, flowering, and fruit development. Several books and reviews have been published on the physiological role of GA. However, relatively limited references are available for roots, since GA does not strongly promote root elongation of many plants.
