STERILIZATION PROCESS FOR IN VITRO REGENERATION OF STEVIA (Stevia rebundiana Bertoni)

The current experiment was carried out at plant tissue culture laboratory, Department of Biotechnology in  Sherer-e-Bangla Agricultural University between December, 2015 and January, 2016 to fix up the sterilization method for explants of ‘Stevia’ using different sterilizing agents for micropropagation. The shoots were taken from the pot grown Stevia plants in confined area of the department. Before sterilization, shoots were washed and kept in laboratory and rinsed in water for few days. Shoots were cut into pieces containing axillary winter buds (1–2 cm). First, buds were sterilized with 70% ethanol for few seconds and after that were sterilized with sodium hypochlorite (NaOCl), calcium hypochlorite [Ca(ClO)₂], mercuric (II) chloride (HgCl₂) and hydrogen peroxide (H₂O₂) in duration from 2 to 30 minutes. Among the disinfecting treatments for tissue culture explants, T₆ with calcium hypochlorite [(Ca(ClO)₂] at concentration of 3% for 20 minutes was gave the best( 43%) survived explants with 15% contaminated culture. This result can be used for further experimental purpose for ‘Stevia’ micropropagartion.