Micropropagation of Pistacia lentiscus L. from axenic seedling-derived explants

Pistacia lentiscus L. (Anacardiaceae), a deciduous forest tree, is important multipurpose Pistacia tree. Today, the major limitation facing the widespread expansion of commercial lentisk plantations is the shortage of superior plants primarily because of difficulties experienced in propagating this species by using the traditional vegetative propagation methods. Shoot cultures were established from aseptically germinated seedlings of lentisk. Factors including the different N6-benzyladenine (BA) concentrations, the combination of cytokinin and other growth regulators, media and antioxidants were assessed and optimized for in vitro shoot proliferation. Full strength MS medium with Gamborg's vitamins containing 30 g l−1 sucrose, 100 mg l−1 PVP, 1 mg l−1 BA and 7 g l−1 agar resulted in multiple shoot (bud) initiation at the rate of 2.7 ± 0.17 shoot (4.18 ± 0.17 bud) per explant in 28 days of culture. Moreover, with the use of in vitro proliferated axenic cultures subcultured at least twice, the effects of auxins and mineral medium strength were also assessed for root induction. Efficient rooting (92%) was achieved in a medium containing 1 mg l−1 indole-3-butyric acid (IBA). The method developed for plant acclimatization was satisfactory because a high percentage of plant survival (83.33%) in the growth room was obtained and the regenerated plantlets resumed growth after 4 months (96%). The method described will be useful for rapid multiplication of lentisk for commercial exploitation.

► The progress in micropropagation of lentisk described here seems promising as a model system for large scale clonal propagation. ► In vitro culture of lentisk is thus a complementary strategy to existing propagation techniques. ► Micropropagation protocol given above is an ideal technique for cloning dioecious woody plant, Pistacia lentiscus L., where male trees are preferred due to higher economical value.