Main Article Content
Oroxylum indicum (V.) is a well-known medicinal plant used in ayurvedic formulation Dashmoolarisht as the plant contains active ingredients like Oroxylin-A, Chrysin, baicalein (Anonymous, 2001). The increase in demand of this species by the pharmaceutical industry has been overexploited and destructed which has placed it in the threatened category (RaviKumar and Ved 2000). Natural propagation of this tree is difficult as the seed set is poor and with low seed viability (Ankurdeep and Sharma, 2016). Thus, micropropagation is one of the technique to conserve and propagate this tree species faster where different stages are involved to develop a whole plant from a single part of it. Micropropagation has been practiced in many nurseries and commercial laboratories for rapid and mass multiplication of plants (Batra et al, 2000, Sharma et al, 2010). Hardening is one of the stages of micropropagation which is the final and most crucial as the plants are brought from in vitro to in vivo conditions. Therefore, the present work was carried out to harden Oroxylum indicum tissue cultured plants utilizing various natural planting substrates. The rooted in vitro plantlets were initially kept under greenhouse conditions for 4 weeks. These plantlets were placed in thermocol cups containing individual cocopeat, soil, sand and their combinations - cocopeat: soil (1:1), cocopeat: sand (1:1) and cocopeat: sand: soil (1:1:1). The cups were covered with polybags to ensure humidity. The growth parameters like shoot length, root length, plant height were recorded before and after 4 weeks. Further, the plants from different substrates were placed in plastic pots containing soil. The plants transferred from sand, soil and sand: soil substrates were the only ones that picked up growth till 8 weeks. Then these were transferred to bigger earthen garden pots and kept for a month. The in vitro plants that were initially placed in the sand substrate were able to survive. Thus, till 2 months the pre-hardening was done in the greenhouse. These pots were then placed under natural sunlight and the growth was assessed in terms of plant height and girth till one year. Initially, growth was slow but after 6 months the plant height (above the soil) and girth of the stem increased steadily. By, 12 months the height reached (28.3 ±14.1cms) and the stem became thick (0.8 ± 0.4cms) and woody indicating a healthy growth. Thus, within a year in vitro O. indicum plants could be hardened.
How to Cite
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• P. Ankurdeep, S. Sharma Int J Res Biol Sci, 6(1), 2016, 7-12.
• A. Batra, J. Sardana, M. Audichya, M. Sharma and D. Zulfikar Ali, 3, 2000, 195-200.
• S. Sharma, N. Rathi, B. Kamal, D. Pundir, B. Kaur and S. Arya, Agric Biol J N Am 1(5), 2010, 827-833.