The induction and proliferation of calli in Gerbera jamesonii Bolus

Leaves and petioles of seven varieties of Gerbera jamesonii Bolus （Compositae） cultured on MS medium supplemented with 0.5, 1.5 and 2.0 mg L~(-1) 2,4-D could produce and proliferate calli in all the varieties. The callus induction by leaf explants is better than by petioles, although there are differences among varieties. No callus could be induced from leaf or petiole explants of varieties F30 and Ⅱ cultured on MS medium if supplemented alone with 6-bezyladenine （6-BA） or thidiazuron （TDZ）, or kinetin （KT）. However, the calli were induced on MS medium containing 2.0 mg L~(-1) 6-BA and 0.5 mg L~(-1) NAA （alpha-naphthaleneacetic acid）, and the calli derived from petioles of variety Ⅱ could produce redifferentiated shoots, but of variety F30 could not. The later could only produce shoots directly from the base of the petioles. It is obvious that callus induction and proliferation of gerbera need growth regulators, and are influenced by varieties and explants of different parts of the plants.