Vegetative propagation of Berberis asiatica Roxb. Ex DC., Ginkgo biloba L., Rauvolfia serpentina (L.) Benth ex Kurz, and Rhododendron arboreum Sm. through stem cuttings

The population of medicinal plants such as Berberis asiatica, Ginkgo biloba, Rauvolfia serpentina, and Rhodo-dendron arboreum is declining from their natural habitats due to high commercial exploitation, medicinal value, slow-growing nature, and climate change. The present study was carried to assess the effects of IAA, IBA, and Rootex PD.01 (commercial 1000 mg kg-1 of indole-3-butyric acid formulation) on survival and growth perfor-mance of stem cuttings so as to develop the vegetative propagation protocols for B. asiatica, G. biloba, R. ser-pentina, and R. arboreum. Four hundred eighty cuttings (120 cuttings of each species) with 0.5-1 cm diameter and 10 cm length were sterilized with 1 g L-1 bavistin and treated with 250 mg L-1 concentration of IAA (indole-3-acetic acid), IBA (indole-3-butyric acid) and Rootex PD.01 (1000 mg kg-1 of IBA) respectively. The survival was highest in G. biloba (90 %) followed by R. serpentina (83.3 %), B. asiatica (80 %) and R. arboreum (66.6 %). Stem cuttings treated with Rootex PD.01 exhibited maximum root length in species i.e. B. asiatica (5.2 cm), G. biloba (8.3 cm), R. serpentina (8.4 cm) and R. arboreum (6.7 cm) respectively. Other growth parameters such as shoot height, shoot diameter, number of leaves per node, number of leaves per plant, and root number were also maximum in stem cuttings treated with Rootex PD.01. This study concluded Rootex PD.01 for the propagation of these species thereby ensuring inexpensive and efficient protocols for mass-scale cultivation.