Effect of NaOCl, growth media, and plant growth regulators on in vitro propagation of disease-free KM140 cassava cultivar (Manihot esculenta Crantz)

Abstract

Cassava mosaic disease (CMD) is one of the most dangerous diseases that has caused heavy losses in yield and starch content on cassava. In vitro propagation using disease-free cassava stakes was an optimal method to produce healthy seedlings. In this study, sodium hypochlorite (NaOCl), growth media (MS, ½ MS and Knudson C) and growth regulators (BA: Benzyl adenine, NAA: Naphthalene acetic acid, GA: Gibberellin) were used to determine an appropriate time for sample sterilization and the suitable concentration for shoot multiplication and root induction of KM140 cassava cultivar. The results showed that sample sterilization at 8% NaOCl concentration in 5 min gave the highest survival rate (71.7%) at 14 d of culture. Cassava explants cultured on MS medium supplemented with 1 mg/L BA gained the highest number of shoots (2.3 shoots), shoot height (10.3 mm) and the number of leaves (4.2 leaves/shoot) at 50 d of culture. The MS medium supplemented with 0.07 mg/L NAA and 0.03 mg/L GA was applicable for the rooting stage of KM140 cassava cultivar (19.8 roots/plantlet at 60 d of culture). The results of the study were fundamental to in vitro propagation process of disease-free KM140 cassava multiplication.