Effect of Different Hormonal Treatment on Stevia (<I>rebaudiana </I>Bertoni) Micro-propagation

Pak J Biol Sci. 2017;20(9):457-464. doi: 10.3923/pjbs.2017.457.464.

Abstract

Background and objective: Stevia micro propagation method is an extensive and highly potential in vitro method use to accelerate plant propagation in compare to the other propagation methods. This study tried to examine the effect of different hormonal combinations for shoot and root development of stevia plant.

Materials and methods: In order to identify the best hormonal combination of establishment culture, three different media (MS1, MS2 and MS3) combine with three separate hormonal combinations for each were tested. For the proliferation and rooting culture, a media (MS2) combined with different hormonal combinations with different levels were tested. The experiment was conducted as a completely randomized design with eight replicates in establishment experiment and factorial in base of completely randomized design with four replicates in proliferation and rooting experiment. Data was analyzed by one-way analysis of variance using SAS.

Results: The mean comparison data showed the lowest amount of kinetin and IBA added in selected medium from establishment phase (MS2) was more effective in proliferation traits. The highest number of lateral branches was observed in the IBA 0.25 mg L-1 (3.96) and kinetin 1 mg L-1 (3.91). The mean comparison of naphthalene acetic acid and IBA treatments in rooting study confirmed that the control treatment (no added NAA and IBA) had the maximum effect on the traits studied. The longest root length (1.68 cm) was observed in the control treatment culture.

Conclusion: The Stevia (rebaudiana Bertoni) in vitro culture under effect of hormonal treatments showed a significant improvement on proliferation and rooting rate.

Keywords: Stevia plant; establishment; growth regulator; micropropagation; proliferation; rooting.