An Efficient Method of Pennisetum × advena ‘Rubrum’ Plantlets Production Using the Temporary Immersion Bioreactor Systems and Agar Cultures

The aim of this study is to develop an efficient method for micropropagation of Pennisetum × advena ‘Rubrum’. Agar cultures containing Murashige and Skoog (MS) medium supplemented with 6-benzyl-amino-purine (BAP) in various concentrations (0.5 mg/L to 2 mg/L) and a temporary immersion bioreactor system (TIS) using liquid medium MS with an addition of 1 mg/L BAP were tested. Rooting was performed using ½ MS medium supplemented with different auxin combinations (indole-3-butyric acid IBA and α-naphthalene acetic acid NAA) and activated charcoal. The TIS method was found to be the most efficient, producing 36.9 new plants within four weeks. The resulting plantlets were thin and bright green in color, with no signs of hyperhydricity. The most suitable agar medium yielded 19.5 new plants within eight weeks. For rooting, ½ MS supplemented with 0.5 mg/L IBA and 0.5 mg/L NAA exhibited an 84% rooting rate, whereas the addition of activated charcoal inhibited rooting.