A Protocol for Rapid Clonal Propagation and Microrhizome Production of Curcuma caesia Roxb. (Zingiberaceae): A Critically Endangerd Medicinal Plant of North East India

Abstract

Background: Curcuma caesia Roxb. (Zingiberaceae) is a rare, critically endangered medicinal plant of Northeast India. The rhizome of the plant is famous for its significant medicinal properties. Methods: Various concentrations of plant growth regulators in Murashige and Skoog (MS) medium were tried in the study using rhizome bud as explant for development of an efficient cost effective protocol for in vitro mass multiplication and microrhizome induction of Curcuma caesia. Result: Shoot multiplication and plant generation was achieved from freshly sprouted shoots of Curcuma caesia on Murashige and Skoog’s medium supplemented with different phytohormones. The best response for shoot multiplication (23.80±0.51shoots/explant) was obtained within 8 weeks in MS medium supplemented with BAP (1.0 mgl−1) and 2,4-D (0.25 mgl−1). Microrhizomes were induced at the base of the in vitro derived shoots upon transferred to medium containing various combinations and concentrations of sucrose and BAP and grown under varying photoperiod. Half strength of MS basal medium containing BAP (1.0 mg/l) and 9% sucrose was found to be optimum for induction of large sized microrhizome within 45 days of incubation under 16 hrs of photoperiod.