Liquid Culture Systems for in vitro Plant Propagation

490 Hans R. Gislerød et al.
4.3 Carbon dioxide (CO2)
Increasing CO2 to 700-800 ppm increased the growth by 15-30 % and
reduced the transpiration by about 15-20 % (Mortensen and Gislerød, 1989).
This suggests that it may be necessary to increase the conductivity of the
nutrient solution by about 30 %, compared to growing without
supplementary CO2.
5. Conclusions
Well-balanced nutrient concentrations in the growing media combined
with the optimum growth environment, are beneficial not only to the growth
in the greenhouse and the culture room for in vitro cultures, but the aftereffects
are also of high value. In addition to this, optimum nutrient
concentrations have to be supplied for the mother plants before propagation
by conventional methods as well as for the in vitro culture to achieve
maximum growth. Growing plants in liquid cultures, whether in greenhouses
or in vitro, needs even more careful attention to plant nutrition than growing
on solid or gelled media, and more knowledge of the climatic conditions that
interact with nutrition.
Comparing the most used media for in vitro cultures (Murashige and
Skoog, 1962; Murashige et al., 1972), with nutrient solutions used for NFT
in greenhouses, the relative concentrations between the nutrients are far from
ideal. We strongly suggest that more attention should be paid to the natural
mineral content of the plant being propagated, and the relative nutrient
concentrations. These analyses should be used when designing optimised
media for in vitro cultures. This should improve plant quality from in vitro
cultures by enhancing proliferation in vitro, as well as having a positive
after-effect on the subsequent growth and quality ex vitro.
References
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Hortic. 361: 145-257
Adams P (2002) Nutritional control in hydroponic. In: Saavas D & Passam H (eds)
Hydroponic production of vegetables and ornamentals. Embryo publications, Athens,
Greece. ISBN 960-8002-12-5
Adams P & Grimmett MM (1986) Some responses of tomatoes to the concentration of
potassium in recirculating solution. Acta Hortic. 178: 29-35