Abstract
Solution flow rate is an important factor to be considered when designing or operating flowing culture equipment. A theoretical model is developed showing that the actual flow rate required for a particular experiment will depend upon many factors, important among which are the nature and concentration of the ion under consideration, the quantity of roots per pot, and the efficiency of these roots in absorbing the test ion under the conditions of the experiment.
The results of experiments conducted at low concentrations of ammonium and nitrate nitrogen clearly demonstrate that flow rates of the order of 1 litre per pot per minute or greater may be required to prevent excessive depletion of the nutrient solution. At lower flow rates, solution depletion resulted in substantial reductions in growth and nitrogen uptake.
Quantities of nutrient solution required for experiments at very high flow rates can be reduced to practical levels by the use of recirculating flowing culture systems, even in installations containing large numbers of pots.
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Department of Agriculture, University of Queensland, St. Lucia, Queensland 4067, Australia.
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Edwards, D.G., Asher, C.J. The significance of solution flow rate in flowing culture experiments. Plant Soil 41, 161–175 (1974). https://doi.org/10.1007/BF00017952
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DOI: https://doi.org/10.1007/BF00017952