Immersion time in sodium hypochlorite in the disinfection of banana meristems for their clonal propagation

Abstract

The experiment was carried out in the Biotechnology Laboratory of the Facultad de Ciencias Agrarias of Universidad Nacional de Asunción, with the objective of evaluating immersion time in sodium hypochlorite in the disinfection of banana meristems (Musa spp.) Nanicao variety for its micropropagation. 80 banana shoots were used, from which the meristematic tips were extracted and planted in Murashige and Skoog culture media supplemented with 1 g.l-1 of activated carbon as an antioxidant. The disinfection treatments consisted of immersion in a NaClO solution (5 %) for 5 (T1) and 10 minutes (T2), respectively. The experimental design used was completely randomized. The variables evaluated during 15 days were: percentage of survival, phenolic oxidation and microbial contamination of the shoots. After the evaluation time, T1 recorded 17.55% surviving shoots and 82.45% microbial contamination attributable to 75% fungi and 25% bacteria. On the other hand, T2 showed 15.82% of surviving outbreaks and 84.18% of microbial contamination attributable to 70% fungi and 30% bacteria. The contaminating fungi of the explants were those belonging to the genera Penicillium and Aspergillus in both treatments. No signs of phenolic oxidation were observed with any of the treatments applied. The Student’s t test was applied at 5% significance, verifying that there are no significant differences attributable to the time of immersion in the disinfectant.