In vitro shoot regeneration from mature tissue of wild Cyclamen persicum Mill.

In vitro shoot regeneration of wild Cyclamen persicum Mill. was studied using mature tissue. Leaf disc, petiole, petal, and peduncle explants were cultured on 1/3 MS medium supplemented with 6-benzyladenine (BA) at 0, 1, 2, or 3 mg l(-1) or thidiazuron (TDZ) at 0, 0.0022, 0.022, 0.22, or 2.2 mg l(-1). The effect of etiolation on shoot regeneration was also studied. Tubers were maintained in light or dark for 6 weeks before etiolated or non-etiolated petiole explants were cultured on MS media containing BA or TDZ of the above concentrations. No shoot formation was observed in media containing BA regardless of concentration, explant type, or etiolation. Leaf discs did not exhibit regenerative potential regardless of TDZ concentration. The greatest percent shoot formation was obtained from peduncle explants cultured on media supplemented with 0.022 or 0.22 mg l(-1) TDZ and petal explants on media containing 0.022 mg l(-1) TDZ. Peduncle explants cultured on media containing 0.22 mg l(-1) TDZ produced the greatest number of shoots. Explant type and TDZ concentration significantly affected callus growth. Cultures of etiolated petioles were free of contamination, had superior shoot regenerative potential, and produced more vigorous callus compared to those of non-etiolated petioles. Etiolated petiole explants exhibited the greatest percent shoot formation (74%) and number of shoots when cultured on media containing 0.022 mg l(-1) TDZ. (C) 2000 Elsevier Science B.V. All rights reserved.