Micropropagation of Manihot esculenta.

Abstract

Manihot esculenta (Cassava) is a key starchy crop cultivated across diverse regions worldwide. Due to the prolonged dormancy of its seeds and the slow pace of germination, farmers commonly propagate M. esculenta using stem cuttings. However, this method has led to an increase in viral and bacterial diseases, negatively affecting yield and threatening the loss of high-quality genotypes. This is one of the main drawbacks of this species for the pharmaceutical industry. Therefore, this work aimed at developing reliable methods for mass production of healthy, virusfree M. esculenta (Var. MU51) for industrial uses. The focus was on creating a micropropagation protocol for the variety MU51, involving optimal surface sterilization, effective hormonal combination for shoot proliferation and ideal media for meristem culture. According to the study, a 10% NaOCl solution, coupled with exposure duration of 15 minutes manifested the most noteworthy success rate in preventing contamination (P < 0.05). This outcome distinctly surpassed the efficacy observed with 5% and 15% Clorox solutions administered for 10 and 15 minutes respectively (P < 0.05). In the context of proliferation of shoots from M. esculenta nodes the application of 0.5mg/L BAP and 0.1mg/L NAA, 1mg/L BAP and 0.1mg/L NAA following a 5- weeks span, the nodal segments that underwent shoot proliferation exhibited comparable growth in both treatments without significant difference (P > 0.05). The initiation of meristem growth was carried out utilizing a solid Murashige and Skoog (MS) medium fortified with a blend of 0.1mg/L BAP (Benzylaminopurine), 0.25mg/L GA3 (Gibberellic acid), and 0.2mg/L NAA, in addition to a standard MS medium. Significantly, the hormonal MS medium demonstrated a significantly superior survival rate (P < 0.05). The current investigation underscores the optimal conditions for mitigating contamination risks and promoting desirable outcomes in M. esculenta shoot proliferation and meristem growth, thereby contributing valuable insights to the field.