The Effect of Cytokonins on Stevia Rebaudiana Bertoni Organogenesis in Vitro

Abstract

Stevia rebaudiana Bertoni is a important medicinal plant which is mostly know as a sugar substitute. The sweeting components (glycosides) are 300 times sweeter than sucrose. Steviol glycosides are applied as a natural sweetener, because SGs does not affect blood sugar level. Stevia propagation by in vitro techniques could be attractive alternative for production sufficient amount of genetically homogeneous plants in a short period of time. Research was carried out in Institute of Biology and Plant Biotechnology of Aleksandras Stulginskis University and Laboratory of Agrobiotechnology of Join Research Center in 2016-2017. Stem segments cultured on MS medium supplemented with BAP, TDZ, KIN (1.0 μM; 2.0 μM; 3.0 μM; 4.0 μM; 5.0 μM; 6.0 μM), 30.0 g l-1 sucrose and 8.0 g l-1 agar. Our results showed that on MS media without growth regulators shoot formation frequency from stem segments was an average 7.78 %. Incorporation of cytokinin into culture medium significantly improved organogenesis process in comparison with control; however positive effect was strongly affected by cytokinin type and concentration. The highest (76.67%) shoot formation frequency as well as number of shoots per explant has been obtained on the medium supplemented with 3.0 μM TDZ. On the medium supplemented with BAP and KIN shoot regeneration was significantly lower as compare with TDZ. Results of this study reveal a potential procedure for Stevia rebaudiana Bertoni stevia direct regeneration from stem segment tissues.