ROOTING OF Stevia rebaudiana BERTONI MINI-CUTTINGS WITH INDOLE BUTYRIC ACID IN HYDROPONICS

Abstract

Consumption of stevia (Stevia rebaudiana Bertoni) is increasing worldwide; however, sexual reproduction is limited by several factors such as difficulties in germination and slow initial growth. The objective of this study was to evaluate indolebutyric acid (IBA) on rooting of mini-cuttings of stevia cv. Morita II under
hydroponics. A single-factor completely randomized experimental design was used with eight IBA concentrations within a range of 0.0 to 6.0 mg L-1, and 100
explants per treatment. Healthy mother plants were selected to obtain apical mini-cuttings of 8.0 ± 0.52 cm in length. Polyethylene gutters were used as hydroponic units with dimensions of 50 × 20 × 16 cm. The nutrient solution contained 2 g L^-1 of Hydro Environment® fertilizer for hydroponic cultivation of vegetables, adjusted to a pH of 6.54 and constant flow aeration was enabled. The response variables were percentage of rooted explants, number and length
of roots and percentage of acclimatized plants in soil. Results indicated that using IBA had a significant effect (P ≤ 0.05) on measured variables; the best treatment was 3.0 mg L^-1 of IBA, with mini-cuttings with 6.8 ± 1.3 cm long, roots 8.2 ± 1.7 cm long and 100 % acclimatized to the soil. It is concluded that
it is possible to obtain stevia mini-cuttings at 30 days with a well-developed root system acclimatized to the soil.