Propagation of a U16 hybid Eucalyptus line by plant cell tissue culture

Abstract

Eucalyptus is one of the important plant species for paper pulp, fuel wood, and timber. In this study, a hybrid Eucalyptus, U16 line, was investigated for rapid in vitro propagation. The apical and adventitious shoots served as initial explants. These were free-disease symptoms that were collected for surface sterilization. Different disinfectants including mercuric and Javel solutions at different concentrations and treated times were performed. The results showed that explants were cleaned under taping water with soap, rinsed in 70^oEtOH for 1 minute, and then immersed in 10% Javen solution for 15 minutes and 0.1% HgCl₂ for 10 minutes gave the highest disinfection rate that was 46.5%. The modified MS medium included basal MS, 30 g/L sucrose, and 7 g/L agar supplemented with 20 ml/L of coconut water (MS medium*) was the most suitable for the rapid multiplication of Eucalyptus lines U16, the shoot multiplication coefficient reached 1.56. In vitro multiplication of eucalyptus U16 was carried out by culturing disinfected shoot segments on the MS* medium supplemented with BAP 1.5 mg/L and kinetin 1.0 mg/L which gave the highest shoot multiplication coefficient (3.24 shoot per explant). The in vitro rooting medium of the U16 line was basal MS supplemented with 1.0 mg NAA/L, the rooting rate was 90.49%, the number of roots was 8.3, and the roots expressed strong growth