Biotechnology Journal International

In vitro direct plantlets’ development from different explants of cotton was studied using nine cultivars which have been developed in Sudan. The influence of various phytohormones on morphogenetic response of different explants of each cultivar was tested. The best medium for multiple shoot induction from shoot tip explants was Murashige and Skoog (MS) basal medium supplemented with 0.1 mg/L Zeatin. In this medium, the highest regeneration percentage (92%) and the maximum number of shoots (2) were recorded for Sudac K cultivar. Shoot elongation and rooting of most of the shooted explants were obtained in 0.05 mg/L Gibberellic acid (GA₃)-supplemented MS medium. Embryo axis explants were best regenerated in MS medium supplemented with 0.1 mg/L Kinetin + 0.1 mg/ L 2,4-D in seven of the nine tested cultivars. The highest shooting percentage (80%) was recorded for Shambat-B followed by Hamid cultivar (75%). The majority of the shoots (62.4%) showed root formation in MS medium supplemented with Kinetin + 2,4-D medium. Non- rooted shoots derived from shoot tip and embryo axis explants showed a range of 90-100 rooting percentages when transferred into 0.1 mg/ L IBA- supplemented MS medium. Cotyledonary nodes explants of cultivars Abdin, Kheiralla, Barakat-90, Knight and Barakat were found to form shoots in 0.1 mg/L Kinetin-supplemented MS medium, with the highest percentage (79%) recorded for Barakat cultivar. Rooting was induced, for all shooted explants, in ½ strength MS medium supplemented with 0.1 mg/L NAA.