In Vitro Organogenesis of Critically Endangered <i>Lachenalia viridiflora</i>

Abstract

Micropropagation via organogenesis of Lachenalia viridiflora W. F. Barker, a native endangered plant from South Africa, is presented in this study. Leaves, collected from in vivo plants, were a source for culture initiation to obtain three types of explants (leaf, bulb, callus). They were grown on Murashige and Skoog (MS) medium supplemented with two concentrations of sucrose (3 or 6%, marked as S3 and S6) and different concentrations of benzylaminopurine (BA) (0.0–5.0 μM) and naphthalene acetic acid (NAA) (0.0–0.5 μM). The results demonstrated that bulbing was more efficient on media with 3% sucrose and this process was closely related to explant type—irrespective of media type twice more adventitious bulbs (5.1–5.6) were regenerated on leaf and bulb explants than on callus (2.6). The highest value of adventitious bulb number was recorded for interaction: leaf × S3/2.5 BA/0.5 NAA (9.3 bulbs per explant). Irrespective of media type, the higher the number of adventitious bulbs (obtained from leaf and bulb explants), the lower their diameter. Moreover, adventitious bulbs regenerated from bulb explants formed the longest leaves (18.9 mm) and in the greatest percentage (52.3%). The highest biomass weight increase indicator (50 times) was recorded for interaction: leaf × S6/2.5 BA/0.25 NAA. Various combinations of plant growth regulators favor biomass increase.

Keywords

• Asparagaceae
• micropropagation
• adventitious bulbs
• PGRs
• sucrose