Establishing in vitro cultures of Pennisetum ‘Vertigo®’ and its shoot multiplication under different LED light quality

This study provides a method for ornamental grass Pennisetum ‘Vertigo®’ in vitro culture initiation and shoot multiplication under different LED light qualities. The culture was initiated from field-cultivated plants collected from the 1st to 30th October at weekly intervals. Later dates of collecting shoot tips increased the effectiveness of surface disinfection (from 46% on the first date to 93% on the fifth one) and the percentage of regenerating explants (from 34% on the first date to 93% on the fifth one). Disinfection and regeneration results were better for the apical buds than the axillary buds. Soaking explants in nystatin before surface disinfection or using a medium with an antibiotic increased the effectiveness of disinfection (even by 27–46%, depending on the combination) and did not inhibit the regeneration of explants. At the shoot propagation stage, the multiplication rate was twice as high for the shoots originating from the apical buds (5.5 per explant) than for those originating from the axillary buds. The addition of yellow light to the red and blue light (RBY) spectrum increased the multiplication rate, and the addition of green light to the red and blue (RBG) spectrum increased the fresh weight of the shoots. The highest content of chlorophyll a was found in the shoots propagated under RB, as well as RBY and RBG light.