Sodium hypochlorite effectively revives slightly contaminated stage II and IV tissue-cultured ‘Cavendish’ banana

Abstract

Contamination in plant tissue culture reduces explant survival and leads to significant losses in propagation efficiency. This study identified the dominant microbial contaminant in tissue-cultured ‘Cavendish’ banana and evaluated the effectiveness of sodium hypochlorite (NaOCl) in rescuing slightly contaminated cultures during multiplication (Stage II) and acclimatization (Stage IV). Fungal contaminants were isolated, purified, and identified, with Chrysosporium sp. emerging as the predominant species (53.85%), followed by Aspergillus sp. and Rhizopus sp. Slightly contaminated explants were treated with NaOCl at 0.60%, 0.80%, 1.00%, and 1.20% (v/v). NaOCl treatments improved explant survival and allowed recovery within three days. At Stage II, all tested concentrations enhanced callus formation and survivability, while at Stage IV, 1.0–1.2% (v/v) NaOCl resulted in better plant growth, including higher meristem height, increased leaf production, and improved rooting. Among the treatments, 1.0% (v/v) NaOCl was identified as the most consistent balance between contamination control and explant viability. Unlike most studies that focus on preventive sterilization at the initial stage (Stage I), this study demonstrates the potential of NaOCl as a curative approach for managing contamination at later stages of micropropagation. This offers a practical strategy to reduce losses and improve efficiency in commercial banana tissue culture systems.