Brassinosteroid Combined With Indolbutyric Acid in Blueberry Micropropagation

The lack of availability of good quality seedlings for blueberry cultivation is an obstacle in the market, preventing the increase of production and cultivated areas. In order to improve rooting of blueberry in vitro, different concentrations of BIOBRAS 16® associated with indolbutyric acid in blueberry micropropagation were evaluated. For such a purpose, the Wood Plant Medium (WPM) culture medium plus the following plant regulators- 0.1, 0.3 and 0.5 mg L-1 brassinosteroids (BIOBRAS 16®) in conjunction with indolbutyric acid (IBA) concentrations of 1.3 and 5 mg L-1, with four replications were taken into account. At the end of 82 days of cultivation and development of the explants in these culture media, the following response variables were assessed- callus percentage (CP), callus diameter (CD), rooting percentage (RP), number of shoots (NS), number of leaves (NL), shoot length (SL), root length (RL) and fresh mass of shoots (FMS). CP was found to be stimulated in so far as concentrations of BIOBRAS 16® and IBA increased up to 0.5 mg L-1 and their diameter increased at concentrations of 3.0 and 5.0 mg L-1 for IBA. Thus, it is concluded that a combination of 0.3 mg L-1 BIOBRAS 16® combined with IBA concentrations of 3.0 and 5.0 mg L-1 contributes to promote root growth and rises in leaf number and fresh mass of micro-propagated blueberry. The use of a 0.3 mg L-1 of BIOBRAS 16® associated with concentrations of 3.0 and 5.0 mg L-1 of IBA showed a high percentage of root formation in blueberry.