Study of the effect of physical state of medium and different concentrations of sucrose, ferric ethylenediamine- tetraacetic acid (FeEDTA) and CuSO4 in enhancing the micropropagation system of Stevia rebaudiana

Abstract

Stevia rebaudiana is a sweet herb native to Paraguay and Brazil. Its leaves are well known for containing sweet glycosides which are intensely sweet compounds with zero caloric value. A comparison of effect of state of medium on the in vitro growth of S. rebaudiana was studied under controlled conditions. Different concentrations of benzyl amino purine (BAP) and kinetin (Kin) (1, 2 and 3 mg/L) were used for the purpose. Explants inoculated in liquid media placed on orbital |shaker showed the best results for the vigorous growth of the plant in all the hormone treatments. In all the hormone treatments, shaking media gave the maximum values of number of multiple shoots as well as shoot length. Shaking cultures also showed response in minimum days of inoculation as compared to solid and static liquid cultures of honey leaf, S. rebaudiana. Medium conditions were also optimized for the maximum micropropagation potential of the S. rebaudiana explants in shaking medium by adding different concentrations of Fe- EDTA, CuSO4 and sucrose. Optimal concentrations were determined as 60 g/L sucrose, 9 ml/L Fe-EDTA and 27.5 µg/L CuSO4. Key words: Benzyl amino purine (BAP), kin, liquid medium, Stevia rebaudiana, CuSO4, ferric ethylenediamine- tetraacetic acid (FeEDTA), sucrose.