Innovative in vitro shoot regeneration in variegated snake plant (Sansevieria trifasciata cv. Laurentii) through utilization of light exposed single-node rhizome tissue

Maintaining genetic fidelity in in vitro-regenerated plants derived from chimeric tissues presents a significant challenge during tissue culture experiments. Sansevieria trifasciata cv. Laurentii exhibits striking periclinal chimeric tissues along its leaves, which are compromised when propagating plants through leaf cuttings. In addition to establishing in vitro production of S. trifasciata cv. Laurentii, the regeneration efficiency of light exposed single-node rhizome explants was also evaluated. Among various types of rhizome explants, the single-node rhizome explant produced the highest mean number of shoots per explant (2.5) on MS medium supplemented with 3 mg L^{- 1} BA and 0.1 mg L^{- 1} NAA, which was approximately five times higher than that of other explants. Notably, all regenerated plants originating from nodal and terminal meristems were morphologically similar to their corresponding mother plants and retained their chimeric characteristics. In contrast, shoots derived from explants containing both nodal segments and terminal meristems (MN explants) exhibited some degree of morphological variation. Specifically, higher concentrations of BA (6 mg L^{- 1}) were found to decrease the phenotypic stability of regenerated shoots by 50%. De novo rhizomes derived from light exposed single-node rhizome (NC explants) yielded the highest mean number of shoots (6 shoot per explant) on MS medium supplemented with 4 mg L^{- 1} NAA and either 0.5 or 0.35 mg L^{- 1} BA. Shoots from de novo rhizomes closely resembled the mother plants, while callus-derived shoots showed only 65% similarity. The presence of light-influenced elevated sugar levels in NC explants supports the hypothesis that the enhanced regeneration capacity in light-exposed single-node rhizome tissues is likely attributed to the upregulation of cytokinin synthesis-related genes and light-induced carbohydrate allocation, which alters hormonal homeostasis and triggers the mitotic activities necessary for de novo rhizome regeneration and shoot multiplication.