Comparative use of a commercial bioreactor system and conventional micropropagation for the production of potato microtubers and grape myrtle (Lagerstroemia indica) microshoots

Potato minitubers and Lagerstroemia indica (grape myrtle) microshoots produced in vitro by a bioreactor system by Osmotek Ltd. (Israel) were compared by qualitative and qualitative means to respective ones produced conventionally in glass culture jars. 'Spunta' potato single node segments were cultured for 12 weeks, in complete darkness, in both liquid (LifeReactor(C)) and semi-solid phase (500 ml glass jars). The composition of media used was a) MS + 1.3 mg l(-1) alar (daminozide) and b) CR (Charles and Rosssignol, 1993) + MS micro-salts and vitamins + 0.16 mg l(-1) alar. Sucrose concentration was 120 g l(-1). The number of microtubers produced in the bioreactor was two times higher than produced in the jars but they were malformed, resulting in lower sprouting rates (3%) than the ones produced in agar solidified medium (41%). Lagerstroemia indica explants consisting of three nodes were cultured for 4 weeks in WPM + 1 muM BA + 0.3 muM NAA in liquid (LifeReactor(C)) and semi solid media exactly as described above under 40 mumol m(-2)sec(-1) of fluorescent light. No difference between numbers of plantlets produced by the two procedures was noticed, although the ones derived from liquid media were extensively hyperhydrized. Respective percentages of survival rates were 96.1% and 23.5% after acclimatization for plants from cultures on semi solid media compared to those out of the bioreactor.