Propagation of S. rebaudiana Bert. can be cultivated by seed germination and stem cutting however, seed germination of this plant is not efficient due to low fertility and produce a heterogeneous population, thus producing unstable sweetening level. Thus, micropropagation can overcome these problems by producing large number of clone plantlets within a short time. In this research, the objective is to study the effect of different concentrations of plant growth regulators; auxin and cytokinin on in vitro responses of S. rebaudiana Bert. The nodal segments used as explant and inoculated onto full strength of Murashige and Skoog (MS) media. The medium supplemented with five concentrations of 6-benzylaminopurine (BAP); 0, 1, 2, 3 and 4 mg/L and also indole-3-butyric acid (IBA); 0, 0.5, 1.0, 1.5 and 2.0 mg/L. After six weeks of culture, number and length of shoots, number and length of roots and callus percentage were recorded. The results showed that 3.0 mg/L BAP produced the highest number of shoots per explant and for rooting, the best treatment that can be used was 1.5 mg/L IBA without cytokinin.
Key words: 6-benzylaminopurine; indole-3-butyric acid; in vitro responses; Stevia rebaudiana
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