N. CHANDRALEGA, D. SUBHA AND N. GEETHA
Abstract
Rauwolfia serpentina L. (Sarpagandha) is an endangered woody perennial shrub belonging to Apocyanaceae family as a source of antihypertensive drug. Due to the high demand and over harvesting of raw materials of this medicinal plant in pharmaceutical industry, there is an urgent need to develop an efficient protocol to overcome exhaustion of R. serpentina. The shoot tip explants were cultured on MS medium fortified with different concentrations of (0.5-2.5 mg/L) BAP and KIN either solely or in combination with 0.5mg/L NAA. The highest frequency of shoot regeneration (90.56%), multiple shoot bud induction (14.63 shoots/ explant) and shoot length (7.35 cm) were obtained, when these were cultured on MS medium augmented with 1.5 mg/L BAP in combination with 0.5 mg/L NAA. After four weeks, in vitro grown shoots were transferred to MS medium supplemented with various concentrations of NAA (0.5-2.0mg/L) for rooting. MS medium containing 1.5 mg/L NAA showed the best response of rooting (94.63 %), maximum number of roots (8.34 roots/shoot) and root length (8.78 cm) within two weeks. The plantlets were hardened in plastic cups containing sterile soil and sand in the ratio of 2:1. After hardening, the plantlets were successfully transferred to field conditions with 95% survival rate. This protocol were established for in vitro plant regeneration from shoot tip explants of R. serpentina and it may be suitable for high frequency of shoot multiplication of this endangered antihypertensive medicinal plant.