Tetraploidization Altered Phenotypic Traits and Metabolite Profile of Java Ginseng (Talinum paniculatum (Jacq.) Gaertn.)

Polyploidization is a beneficial technique for enhancing the biomass of and secondary metabolite concentrations in plants. Java ginseng (<i>Talinum paniculatum</i> (Jacq.) Gaertn.) can be used as an alternative source of nutrition and has both ornamental and medicinal value. To improve the biomass and content of medicinal ingredients, this study established an in vitro system that was used to induce polyploidy of java ginseng. Tetraploids were successfully produced by exposing the axillary buds to colchicine. The most favorable medium for inducing polyploidy was Murashige and Skoog medium devoid of hormonal substances, while immersing stem segments in a solution of 1-3 mg/mL colchicine for 48 h could achieve tetraploidy induction with a maximum rate of 18.03%. Tetraploids were distinguished from diploids by flow cytometry, with the tetraploids exhibiting darker and thicker leaves, bigger fruit and pollen, and larger stomata but lower stomatal density, while the aboveground biomass yield was reduced significantly compared with that of the diploids. Tetraploidization also altered the metabolite profile, with 22 metabolite concentrations being significantly increased (<i>p</i> < 0.05) and 74 metabolite concentrations being significantly decreased (<i>p</i> < 0.05) in the leaves of the tetraploids. The autotetraploid produced in this study could provide novel insights into artificial polyploid breeding and could be utilized as a germplasm to generate new polyploids.