Organogenesis in Cell Suspension Cultures of Atropa belladonna L. and Atropa belladonna Cultivar lutea Döll

Abstract

Callus cultures have been initiated from excised cultured roots of Atropa belladonna and A. belladonna cultivar lutea and used to establish suspension cultures in a synthetic culture medium (referred to as SSM) containing 2.0 mg/1 α-naphthaleneacetic acid (NAA). Visible cellular aggregates develop in these suspension cultures and when such aggregates are cultured in an NAA-omitted medium, large numbers of roots arise superficially on the aggregates. Root development is enhanced by incorporating into the auxin-free medium either tropic acid or I-naphthoxyacetic acid and both these substances can promote root initiation in the presence of levels of NAA which alone suppress organogenesis. The aggregates also give rise under appropriate conditions of culture to shoots and to embryo-like structures. The nature and frequency of such morphogenesis in the aggregates is dependent not only upon the composition of the culture medium but upon the number and the length of previous culture passages through which the callus and suspension cultures have been propagated in the SSM. The ultimate loss of morphogenetic potential in serially propagated callus is discussed. The structure of the aggregates in SSM and in the media promoting root initiation is described. Examination of the aggregates for their content of alkaloids indicates that the major belladonna alkaloids can only be detected in cultures forming roots.