Optimization of bud disinfection technique and influence of growth regulators on micropropagation in ginger (<i>Zingiber officinale</i> Rosc.)

Abstract

Ginger (Zingiber officinale Rosc.) is a spice, considered as a food medicine because of its numerous beneficial actions on health. However, its production faces several constraints, including the lack of efficient planting material. This is a limiting factor for industrial ginger production. The present study therefore aimed at developing an effective in vitro regeneration protocol for ginger. First, three disinfecting agents (sodium hypochlorite, calcium hypochlorite and mercury chloride) were tested. Then, different combinations of naphthalene acetic acid (0.5 mg/L NAA) and/or benzyl amino purine (1, 3 and 5 mg/L BAP) were evaluated on in vitro shoots regeneration. The results revealed that 3.6% sodium hypochlorite, used for 20 min, induced the best disinfection rates (100%) and healthy buds (84.66%). Furthermore, this study showed that the tested hormonal combinations significantly influenced shoots proliferation in ginger. However, the Proliferation Medium 4 (PM4) [Murashige and Skoog medium including vitamin B₅ (MSB) + 0.5 mg/L of Naphthalene Acetic Acid (ANA) + 5 mg/L of Benzyl Amino Purine (BAP)] was the most effective. It induced the highest average number of shoots (22.83 shoots) with an induction rate of 80.50%. As a result of this study, 3.6% sodium hypochlorite used for 20 min and MP₄ medium (MSB + 0.5 mg/L ANA + 5 mg/L BAP) were selected for in vitro ginger regeneration.