TDZ x IBA induced shoot regeneration from cotyledonary leaves and in vitro multiplication in safflower ( Carthamus tinctorius L.)

A high frequency adventitious shoot regeneration protocol for safflower (Carthamus tinctorius L.) cv. Dincer with high yield (Turkish cultivar) using cotyledonary leaves of 10 day-old seedlings were optimized by studying the influence of different combinations of thidiazuron (TDZ) and indole-3-butyric acid (IBA). Cotyledonary leaves were cultured on Murashige and Skoog medium (MS) supplemented with different concentrations and combinations of TDZ and IBA. The highest percentage of regenerated shoots (33.33%) and the highest number of shoots per explant (6.5) occurred on a MS medium containing 0.5 mg/l TDZ and 0.25 mg/l IBA. Furthermore, cotyledonary nodes and meristem tips of 14 day-old seedlings were cultured on Murashige and Skoog (MS) medium supplemented with various concentrations of N6-benzylamino-purine (BAP) alone or combination of -naphthalene acetic acid (NAA). Direct multiple shoots from cotyledonary nodes and meristem tips developed within 18 - 21 days in most media tested. 100% shoot multiplication was achieved from cotyledonary node and meristem tip on a range of MS media supplemented with different concentrations of BAP and NAA.