IN VITRO CALLOGENESIS AND ORGANOGENESIS IN TAXUS WALLICHIANA ZUCC. THE HIMALAYAN YEW

Abstract

Taxus wallichiana Zucc., is a medium sized temperate forest tree species of Asia ranging from Afghanistan through the Himalayas to the Philippines. It has been heavily exploited for its leaves and bark which are used to produce the anti-cancer drug Taxol. Due to its long seed dormancy period, its natural regeneration from seeds is very low. In the present study, biotechnological method is applied to grow the plant In vitro through plant tissue culture techniques. Different plant growth regulators (2, 4-D, NAA, IBA, BAP, Kin) were used to regenerate it through direct or indirect route of organogenesis in the In vitro conditions. Callus was induced successfully both in stem and leaf (needle) explant on MS media supplemented with 1 mg/L, 1.5 mg/L, 2 mg/L, 2.5 mg/L and 3.0 mg/L, 2,4-D. The best callus was induced on MS media supplemented with 2 mg/L 2,4-D and 5 mg/L Activated Charcoal (AC) within 2 weeks of culture in stem explant, but we did not succeeded in the regenerations of shoot in both type of callus culture. The shoot tip meristem was elongated on MS media supplemented with 2 mg/L BAP and MS media supplemented with 1mg/L IBA up to 10-14 cm after 3 to 4 subculture. Roots were induced in the elongated shoot tips in 60-80 days on MS media supplemented with 3.5 mg/L IBA and on half strength MS media supplemented with 8 mg/L IBA. It is concluded from the present study that callus culture from stem and needle explant is not suitable for organogenesis in Taxus wallichiana, however shoot elongation and root induction in shoot tip culture is feasible and suitable for the multiplication of Taxus wallichiana through tissue culture.