Evaluation of sterilants on the establishment of in vitro regeneration protocol in Litsea cubeba (Lour.) Pers

Litsea cubeba holds significant commercial value due to its essential oils and pharmacological properties. Establishing an effective in vitro culture system is crucial for mass propagation and conservation of this species. However, microbial contaminants present a common challenge, often hindering the establishment of in vitro cultures. The present study was conducted to establish and maintain in vitro cultures of L. cubeba. The sterilants, viz., mercuric chloride (HgCl₂) and sodium hypochlorite (NaOCl), were evaluated at different concentrations (0.1, 0.2%) and exposure times (3, 5, 7 minutes for HgCl₂; 10, 15, 20 minutes for NaOCl) to assess their contamination and survival rates. Among all the treatments tested, treatment 11 (T11) with 0.2% NaOCl for 15 minutes was found to be the most effective, with a survival rate of 97.30% and a contamination rate of 6.76%. The study revealed that NaOCl when applied at optimized concentrations, effectively reduced microbial contamination while maintaining higher explant viability. In contrast, although HgCl₂ demonstrated strong antimicrobial action, it resulted in increased tissue dam-age and lower survival due to its phytotoxic nature. Extended exposure and higher concentrations of both sterilants significantly affected explant viability and inhibited shoot regeneration. These findings suggest that NaOCl is a more suitable and environment friendly alternative for sterilization in L. cubeba culture establishment. The study contributes toward developing a standardized sterilization protocol for efficient micropropagation and conservation of this valuable species.