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A refined and an efficient protocol for in vitro clonal propagation of Commiphora wightii, a red-listed desert plant of medicinal importance, has been developed from nodal segment of mature plant. Nodal segments from new branches having 6-7 nodes were excised after discarding the initial 5-6 cm terminal portion and were surface sterilized with 2.5% NaOCl (sodium hypochlorite), (v/v). MS medium [MURASHIGE & SKOOG, 1962] with different concentrations of BAP (6-benzylaminopurine) was used alone and in combinations with IAA (indole-3-acetic acid), NAA (α-naphthalene acetic acid), Kn (kinetin) and other additives for shoot induction. Best bud break response (84.5%) was obtained on MS medium supplemented with 8.88 µM BAP, 0.57 µM IAA and additives (50 mg l-1 ascorbic acid, 25 mg l-1 citric acid and 25 mg l-1 adenine sulphate) within 2 weeks of inoculation. The micro-shoots were subcultured and maintained for further elongation on the same medium for 4 weeks. Best shoot multiplication was obtained on same medium as used for shoot initiation. Best rooting was obtained when the shoots were initially given a 24 h pulse treatment in liquid MS medium supplemented with 4.92 µM IBA (indole-3-butyric acid) and 5.71 µM IAA under dark condition, followed by transfer to semi-solid half-strength hormone-free MS medium supplemented with 2% (w/v) sucrose and 0.5% (w/v) activated charcoal. High (86.7%) percent rooting was achieved after 4-5 weeks with 3-4 multiple adventitious roots of 5-6 cm length. These in vitro raised well rooted plantlets were acclimatized in a two step manner. During in vitro hardening step, the survival was 61.5% and during ex vitro hardening step it was 100%. Hardened plants (10-12 cm in height) were transferred to polythene-bags filled with mixture of soil and FYM in the ratio of 2:1 (v/v) and were kept in 75% agro-net shade for one month, where they gained height up to 60 cm. Five month old hardened plants were planted in open field condition for evaluation of these tissue cultured raised plants. There is cent percent survival of these field grown plants over period of two years with no visible morphological abnormalities. Genetic fidelity test was carried out for these in vitro raised plants by using RAPD primers (OPA and OPN). Uniform banding pattern was observed in all plants without any polymorphism.

A refined and high efficiency protocol for in vitro regeneration of Commiphora wightii, a red-listed medicinal plant of medicinal importance, has been developed through optimized somatic embryogenesis pathway. Cultures from immature fruits were induced and proliferated on B5 medium supplemented with 2.26 µM 2,4-D. Embryogenic calli were obtained and then maintained for extended periods by alternately subculturing on modified MS medium supplemented with 1.11 µM BAP, 0.57 µM IBA and with 0.5% activated charcoal or without PGR every 3-4 weeks. Cyclic embryogenesis was obtained. Late torpedo and early cotyledonary stages somatic embryos were regularly harvested from PGR-free modified MS medium. It was found that percent moisture available in culture containers play a critical role in maturation and subsequent germination of somatic embryos of C. wighti. Maximum germination of more than 80% was achieved through media recycling. Somatic embryo derived plants (emblings) were acclimatized. After 5 months, acclimatized plants were out-planted in experimental field. These morphologically normal plants have been surviving for over 3 years. Molecular polymorphism was clearly evident when these plants were tested using RAPD primers, making the plants suitable for use in its species restoration program. [ABSTRACT FROM AUTHOR]

Commiphora wightii (Arn.) Bhandari, is a medicinal important desert species of the family Burseraceae. It is a well known for its valuable active principle found in its oleo-gum-resin (guggulsterone E and Z), which are used in drugs preparation for lowering the cholesterol level in human body. Due to its overexploitation, poor natural regeneration this valuable plant is on the verge of extinction and thus a IUCN Red listed species. In the present study we report development of an efficient micropropagation protocol from cotyledonary node of Commiphora wightii. Cotyledonary nodes were used as an explants and multiple microshoots were obtained on Murashige & Skoog (MS) medium supplemented with 2.68 μM α-Naphthalene acetic acid (NAA) and 4.44 μM 6-Benzylamino purine (BAP) and on 2.68 μM NAA; 4.44 μM BAP with additives (glutamine 684.2 μM; thiamine 29.65 μM; activated charcoal 0.3%) and various other hormonal combinations. Elongation of microshoot was significantly observed on the 2.46 μM Indole-3-butyric acid (IBA) and 2.22 μM BAP supplemented MS medium. Efficient rooting was obtained on pretreated microshoot (4.92 μM IBA for 24 hours) and followed by transfer to White’s medium without Plant Growth Regulators (PGR) and high concentration of activated charcoal (AC). Rooted micro-shoots were transferred to vermiculite and wetted with Hoagland’s solution for primary hardening for 4-5 weeks and then finally transferred to plastic cups containing vermiculite, placed in mist chamber. Plantlets were transferred to soil: FYM 1:1 containing poly-bags, then to green shade house for complete acclimatization and finally transplanted to the experimental field. [ABSTRACT FROM AUTHOR]