Preservation of the Callus Tissues under the Condition of Superlower Temperature (-196℃) in Fritillaria thunbergii Miq.

Put the callus tissues in Frilillaria thunbergii Miq. which had been cultured for 30-35days in the medium containing 5% DMSO to be precultivated for 7 days, then process themwith the protective freezer containing 10% DMSO+5%glycerine. It is found that the