Effect of growth regulators on micropropagation of Rauvolfia serpentina (L.) Benth

Abstract

Rauvolfia serpentina (L.) Benth. called Sarpagandha (the snake root) in Hindi, belongs to family Apocynaceae. This plant is listed in earliest Ayurvedic medicinal text the Charaka Samhita (c. 700 B.C.) and has been used since in olden days for the treatment of mental illness and insomnia. The roots of R. serpentina contain numerous alkaloids. Its indiscriminate use and poor method of conventional propagation have led this species to be included in the list of endangered plants. Thus a need arises to generate an efficient protocol for cloning of R. serpentina in order to regenerate propagules to replenish depleting forests and meeting the demand of commercial cultivation. The present study reveals the development of an efficient and simple process for large-scale clonal micropropagation of selected plants of R. serpentina and their successful field establishment. In vitro shoot multiplication from nodal explants of Rauvolfia serpentina was standardized by using MS) medium 13 supplemented with a cytokinin (BA or Kin). Inclusion of NAA in the culture medium along with BA promoted a higher rate of shoot multiplication. The mean number of shoots per explant after 4 weeks of culture was maximum (5.21) on the MS medium supplemented with 2.0 mg l-1 BA and 0.25 mg l-1 NAA. The elongated shoots rooted within 7-8 days in 1/2 strength MS medium supplemented with 0.25 mg l-1 of NAA and 2% (w/v) sucrose. About 85% of the rooted plantlets survived acclimatization and transfer to the greenhouse. The present study paves a way for conservation and propagation of this important medicinal plant.