In vitro propagation of citrus rootstock Citrumelo swingle

Abstract

This study was conducted to propagate Citrumelo swingle rootstock in vitro. At the initiation experiments, single nodes were cultured in MS or MT medium supplemented with five concentrations of BA (0, 1, 2, 3, and 4 mg l^-1). After four weeks of the initiation, the MS medium showed a significant response increase in percentage (92%). While the MT medium gave 56%, as soon as, the highest significant No. of shoots obtained from MT medium (2.04 shoot). During the multiplication experiments, shoots in 1 cm length were cultured in the best medium from the initiation stage (MT + 2 mg l^-1 BA) supplemented with five concentrations of Kin (0, 2, 4, 6, and 8 mg l^-1). After 8 weeks the results of the multiplication stage showed that the MT medium overcame significantly in comparison with the MS medium in the shoot length (1.12 and 0.69 cm respectively), Furthermore, the media supplemented with 2 mg l^-1 of BA and Kin achieved the highest significant value in all multiplication characters (5.15 shoots, 1.13 cm, and 19.80 leaves) respectively. For the rooting stage, MT medium in ½ strength of salts supplemented with IBA (0, 0.5, 1, 1.5, and 2 mg l^-1) was used. After 6 weeks, The results of the rooting experiment showed that 1.5 mg l^-1 IBA resulted in the highest value in the rooting percentage (90%), the highest No. of roots (4.67 roots shoot^-1) has overcome significantly in comparison with 0, 0.5, and 1 mg l^-1 treatments, although.