Standarization of cloning in Commiphora wightii

Indian bdellium [Commiphora wightii (Arnott.) Bhandari] is a large shrub of the family Burseraceae wildly growing in arid and semi arid tracts of Rajasthan and Gujarat in India and included in the Red Data Book (IUCN 2011). The over exploitation and unscientific methods of gum tapping led to destruction of its natural population. Here, studies were conducted for standardization of macro-propagation protocols through stem cuttings to develop a suitable macro-propagation technique for cost effective production at large scale. Experiments were imposed to elucidate the effect of cutting diameter (0.50 cm to >1.50 cm) in combination with growing conditions (sunlight, shade house and mist chamber) on shoot sprouting and adventitious rooting. Results revealed that the cutting diameter of 0.75-1.00 cm in mist chamber performed best for sprouting (90.00%) and rooting (73.33%), number of primary root (6.67) and number of secondary root (16.67) followed, by 1.00-1.51 cm in mist chamber conditions. Less performance of sprouting (40.00%), rooting (33.33%), number of shoot (1.33), primary root (1.00) and number of secondary root (1.00) was recorded in cutting size of > 1.50 cm diameter in sunlight. Another experiment was performed with different concentrations (100, 200, 500 and 1,000 mg L-1) of indole-3-acetic acid (IAA) and indole-3-butyric acid (IBA) on adventitious root formation on cuttings of 0.25-0.50 cm of diameter in comparison to control (without application of plant growth regulator). Maximum rooting percentage was recorded in IBA 200 mg L-1 (93.33%) followed by IBA 500 mg L-1 (86.66%) as compared to control which showed sprouting (60.00%) only. Third experiment was performed with newly formed mini-cuttings treated with concentrations of IAA and IBA. The propagules of less than 8-10 cm in length and basal diameter less than 0.25 cm were selected as mini-cuttings. The mini-cuttings treated with IBA (500 mg L-1), showed 64.30% rooting as compared to other treatments. Thus, the main finding of these experiment was that Commiphora wightii can also be propagated through mini-cuttings technique having diameter of < 0.25 cm in mass level and using plant growth regulator