Optimization of in vitro Propagation of Purple Passion Fruit (Passiflora edulis), an Important Medicinal and Ornamental Plant

Tissue culture techniques can be beneficial for quick clonal propagation and production of disease-free plants of purple passion fruit as one of the most important medicinal and ornamental plants. These techniques are essential tools for the production of transgenic plants and high-value phytochemicals. The present study was planned to introduce an efficient in vitro propagation for purple passion fruit(Passiflora edulis Sims.). To do so, the effect of different plant growth regulators was investigated on micropropagation medium of purple passion fruit. For proliferation stage, nodal segments were cultured in media supplemented with various combinations of different plant growth regulators including: BA (0, 2.2, 4.4 and 8.9 μM), TDZ (2.3, 4.5 and 9.1 μM), GA3 (0 and 2.9 μM) and IBA (0 and 0.5 μM).  For rooting, shoots with about 1.5 cm long originating from explants were removed and cultured in half-strength MS medium containing different concentrations of auxin-based plant growth regulators including: IAA (0, 1.1, 2.9, 5.7 and 11.4 μM), IBA (1, 2.5, 4.9 and 8.9 μM), and NAA (1.1, 2.7, 5.4, 10.7 μM). For the proliferation stage, the best plant growth regulator combination was 8.9 μM BA+2.9 μM GA3+0.5 μM IBA, resulting in the maximum shoot proliferation, number of shoots per explants, and shoot length. Half-strength MS medium supplemented with 5.4 μM NAA or 8.9 μM IBA was the most effective treatment for the rooting of shoots. Gradual acclimatization of the rooted plantlets was performed and the plantlets were established in the soil successfully. The micropropagated plants did not exhibit any visually detectable variation to their mother plants.