First report of an efficient in vitro regeneration protocol via callus-mediated organogenesis for Limnophila rugosa

Abstract

Abstract Limnophila rugosa is a valuable medicinal plant listed in the Vietnam Red Data Book and threatened by overexploitation and habitat loss, highlighting the urgent need for effective propagation and conservation strategies. This study aimed to establish an efficient in vitro regeneration protocol via callus-mediated organogenesis using leaf and petiole explants. Explants were cultured on Murashige and Skoog (MS) medium supplemented with different plant growth regulators (PGRs), and callus induction, shoot regeneration, and rooting responses were evaluated. The highest shoot regeneration was achieved on MS medium supplemented with 0.3 mg/L TDZ and 0.1 mg/L IAA, resulting in a regeneration frequency of 60.00 ± 7.70% and 14.25 ± 1.51 shoots per explant. Rooting was optimal on MS medium containing 0.1 mg/L IBA, with a rooting frequency of 64.00 ± 6.78%. To our knowledge, this study represents the first report of an efficient callus-mediated regeneration protocol for L. rugosa. The established protocol provides a promising platform and has the potential to support large-scale clonal propagation, germplasm conservation, and future biotechnological applications of this threatened medicinal species.