A Novel Surface Sterilization Technique for in vitro Establishment of Dianella tasmanica variegata Nodal Explants

Abstract

Dianella tasmanica ‘variegata’ is one of the popular species which is exported as ex-agar plants from Sri Lanka. In order to promote dianella exports, micropropagation should be increased to produce a high-quality large number required by the export markets. However, severe microbial contaminations in the in vitro establishment have become the bottle neck for large scale in vitro propagation of this species. Therefore, this study was undertaken with the objective of using sulfur nanoparticles (S-NP) to eliminate surface adhered fungal and bacterial contaminants to obtain a vast number of contamination-free cultures at the in vitro establishment stage. Apical parts of about 6 cm of D. tasmanica were used in this study. Effects of S-NP solution in 500 mg/L was used with the control of 10% Clorox™ for the surface sterilization of the nodal explants. Results revealed that 500 mg/L S-NP produced 80% and CloroxTM produced 40% contamination-free cultures after 4 weeks of establishment in vitro. The experiment was repeated twice. This study suggests that S-NP is a promising lowcost non-toxic material that can be used in the surface sterilization of dianella nodal explants.