Abstract:
The aim of this study was to evaluate the effects of fermented extract contend GA3 obtained by Solid State Fermentation and comparing with a commercial source of GA3 (reagent grade) in In vitro culture of common lavender (Lavandula angustifolia Mill.). The residual effects of GA3 also were evaluated in acclimatization. Nodal segments of L. angustifolia were cultured on LS culture medium, supplemented with 1320 mg.L-1 CaCl2, 30 g.L-1 sucrose and solidified with 7 g.L-1 agar. The experimental design was completely randomized in a factorial arrangement (2x4), with the first factor being the type of GA3 source (pure or fermented extract) and the second factor being the GA3 level (0, 0.25, 0.5 and 1.0 mg.L-1). Growth parameters were evaluated after 85 days. Acclimatization was performed using Plantmax® HT as substrate, plantlets were maintained by 14 days inside greenhouse with intermittent nebulization and after they were transferred to another greenhouse with manual irrigation. Growth parameters were evaluated after 28 days. The fermented extract and GA3 pure were analyzed by HPLC (High-performance liquid chromatography). In conclusion, the differences between the GA3 sources (fermented extract and reagent grade) in nodal segments of Lavandula angustifolia cultured In vitro and the plantlets acclimatized are little. The GA3 pure increases more the root number than fermented extract. The GA3 pure promotes highest chlorosis rate than fermented extract. Fermented extract inhibits root formation at higher levels (1.0 mg.L-1). In acclimatization, the fermented extract at 0.25mg.L-1 GA3 showed a beneficial residual effect promoting plants more vigorous than other treatments.
