Establishment of glyphosate selective concentrations for winter rapeseed (Brassica napus L.) transgenic tissues efficient selection in vitro

Aim. To establish the optimal concentration of glyphosate for efficient selection of transgenic tissue culture in biotechnology of rapeseed by in vitro selection of glyphosate-resistant and non-resistant winter rape. Methods. As an explants 7–10 mm fragments of 6-day rapeseed hypocotyls were used to cultivate on the medium, supplemented with 1 mg/L of 2,4-dichlorophenoxyacetic acid (2,4-D) for 12 days at 24°C under dark conditions for the initiation of callusogenesis. For regeneration of plants, the MS nutrient medium was supplemented with 3 mg/L of 6-benzylaminopurine (BAP), 2 mg/L of zeatin, 0.1, 0.5 and 1 mM of glyphosate, respectively. As a control, glyphosate-free regenerative nutrient medium was used. The results were statistically processed using Microsoft Excel. Results. It has been shown that glyphosate-susceptible rape explants form leaves and shoots with a frequency up to 8.3 % ± 0.8 % on the medium supplemented with 0.1 mM glyphosate compared to 57.2 % ± 0.6 % in the control. However, the morphogenic structures did not pass selection after transferring shoots to the elongation medium supplemented with 0.1 mM glyphosate. Conclusions. For the in vitro selection of rapeseed 0.1 mM glyphosate can be used in a nutrient medium at the stage of adventitious buds formation. But at the regeneration stage, the amount of herbicide should be increased to avoid false-positive results. Keywords: winter rapeseed, Brassica napus L., in vitro culture, selective marker, herbicide, glyphosate.