PROLIFERATION OF MERISTEMATIC CLUSTERS IN DISPOSABLE PRESTERILIZED PLASTIC BIOREACTORS FOR THE LARGE-SCALE MICROPROPAGATION OF PLANTS

Proliferation of meristematic clusters of several plants in an inexpen sive airlift bioreactor system, consisting of a disposable presteriliz ed light transmittable plastic film vessel is described. The optimal s hape, size, and structural function of the disposable plastic bioreact or are based on the bubble column and airlift glass bioreactors. The d isposable bioreactors are designed in a conical configuration with a s ingle inoculation and harvest port and multiple use dispensing and mix ing accessories. Shearing damage and foaming problems known to exist i n bioreactors due to the plant's rigid cell wall and size were greatly reduced in the disposable plastic bioreactors. The disposable bioreac tors were used for propagule proliferation and growth, using meristem and bud clusters of potato, fern, banana, and gladiolus. The clusters' biomass increased five-to eightfold over a period of 26-30 d, dependi ng on the species. The clusters were separated mechanically by a chopp er made of a grid of knives. The chopped propagules were inoculated to af;ar medium for further growth and developed into transplantable pla nts. In the case of gladiolus and potato, corms and tubers developed i n a sucrose-elevated storage organ induction medium, respectively, aft er the initial formation of small shoots. The plantlets and storage or gans were transplanted to an acclimation greenhouse and continued to g row with a 95-100% survival, depending on the species. Plant developme nt was followed for a period of 16 wk in fern and 12-14 wk in potato, banana, and gladiolus and normal shoot and leaf growth was observed. T he feasibility of large-scale liquid cultures for plant micropropagati on is discussed.