Optimizing In Vitro Propagation of Haworthia truncata Schönland Using Leaf, Root, and Inflorescence.

Area of Science:

• Plant Biotechnology
• Horticultural Science
• Plant Physiology

Background:

• Haworthia truncata, a South African native, faces limited growth and scarcity, leading to high production costs.
• Global trade of Haworthia species is significant, with China and Turkey as major exporters.
• Tissue culture presents a viable method for mass propagation of desirable succulent species like H. truncata.

Purpose of the Study:

• To optimize tissue culture protocols for efficient mass propagation of Haworthia truncata.
• To evaluate the effects of different plant growth regulators (IBA, NAA, BA) on callus induction and shoot proliferation.
• To determine the most effective explant types (leaf, root, inflorescence) for regeneration.

Main Methods:

• Murashige and Skoog (MS) basal media were supplemented with varying concentrations of indole-3-butyric acid (IBA), naphthaleneacetic acid (NAA), and benzylaminopurine (BA).
• Explants including leaf, root, and inflorescence were cultured on media with different plant growth regulators (PGRs) or without PGRs (control).
• Callus induction, shoot proliferation, and rooting percentages were assessed to determine optimal regeneration conditions.

Main Results:

• Inflorescence explants showed highest callus induction (1.5 mg/L IBA) and shoot proliferation (1 mg/L IBA).
• Leaf explants performed best with 0.05 mg/L NAA and 0.25 mg/L BA for callus induction, and 0.05 mg/L NAA and 1 mg/L BA for shoot proliferation.
• Root explants achieved maximum callus induction (0.25 mg/L BA and 0.25 mg/L NAA) and shoot proliferation (0.05 mg/L NAA and 1 mg/L BA).
• The highest rooting percentage of regenerated shoots was achieved on ½ MS medium supplemented with 1.5 mg/L IBA.

Conclusions:

• Specific combinations of plant growth regulators and explant types significantly influence the efficiency of Haworthia truncata regeneration.
• Optimized tissue culture protocols using selected PGRs and explants can facilitate mass propagation of Haworthia truncata.
• This research provides a foundation for the commercial-scale production of Haworthia truncata, addressing scarcity and high costs.