Abstract

The callus was induced on Murashige and Skoog’s (MS) medium supplemented with 2,4-dichlo-rophenoxyacetic acid (2,4-D) or 6-Benzylaminopurine (BAP) from the Chinese medicinal herb Euphorbia helioscopia in the family Euphorbiaceae. The highest frequencies of callus induction were observed on MS medium supplemented with 3.0 mg l^-1 2,4-D. Callus (yellow, loose, granular) was chosen as research focus in the long-term callus maintenance, the proliferation coefficient could still hold about 10 after subcultured 5 turns. Histological analysis was done to reveal the developmental pattern of callus formation. Detailed analysis revealed induction of leaf yielded many endogenous eumeristematic cells which were still embedded in the parenchymatic tissue.

Key words: Euphorbia helioscopia, callus induction, callus maintenance, histological, developmental pattern.