Liquid Culture Systems for in vitro Plant Propagation

84 Meira Ziv
The main advantage of airlift bioreactors is their relatively simple
construction, the lack of regions with high shearing potential, reasonably
high gas and nutrient transfer rates and relatively high yields at low input
rates (Denchev et al., 1992). A bubble-free oxygen supply bioreactor with
silicone tubing was found suitable for embryogenic cell suspensions and
provided foam-free cultures (Luttman et al., 1994). For hairy root cultures an
acoustic mist bioreactor was found to increase root biomass significantly
(Chatterjee et al., 1997). Simple glass, polycarbonate cylinder (Figure 2), or
plastic bioreactors were used for propagation of ornamental, vegetable and
woody plant species. These included the foliage plants – Boston fern,
Philodendron and Spathiphyllum; the ornamentals – Gladiolus, lilies,
Ornithogalum dubium, Narcissus, Nerine, Brodiaea;, and the vegetable
crops – cucumber, asparagus and potato. Poplar root cultures regenerating
buds, and banana were also propagated in bioreactors. In banana, the type of
culture and the volume of the medium affected biomass growth (Table 1).
Increasing the concentration of ancymidol decreased biomass growth,
increased bud or meristem number per cluster and decreased leaf elongation
and expansion (Table 2).
Table 1: The effect of culture type and medium volume on banana bud cluster proliferation
in the presence of 2.5 ppm ancymidol after 30 days
Culture vessel
capacity (ml)
Medium
(volume
ml)
FW (g)
Growth
value (1)
No. buds per
cluster
Initial Final
Erlenmeyer 250 50 6.5 � 0.7 17.5 � 1.8 1.46 5.6 � 0.6
Erlenmeyer 500 100 10.8 � 1.2 57.2 � 3.1 4.29 6.7 � 0.8
Glass bioreactor
1000
500 17.6 � 2.8 123.5 � 2.1 6.01 12.0 � 1.8
Disposable
bioreactor 2500
1250 21.66 � 2.8 269.4 � 4.8 11.4 15.1 � 2.1
(1) Growth value: (FWfinal-FWinitial)/FWinitial.
Table 2: The effect of ancymidol on banana cluster proliferation in disposable plastic
bioreactors after 26 days culture
Ancymidol � Growth
(µmol)
(1)
Buds or meristems per Leaf tissue
(FW g)
cluster
(% FW)
0 172 � 16 12 � 0.8 89
3.95 165 � 12.2 18 � 2.1 86
9.75 111 � 9.7 26 � 3.1 58
19.50 80 � 5.3 48 � 3.9 17
(1) Initial inoculum 30g l -1 medium