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PubMed · 11537992

Stabilization of pH in solid-matrix hydroponic systems.

J Frick·C A Mitchell
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Abstract

2-[N-morpholino]ethanesulfonic acid (MES) buffer or Amberlite DP-1 (cation-exchange resin beads) were used to stabilize substrate pH of passive-wicking, solid-matrix hydroponic systems in which small canopies of Brassica napus L. (CrGC 5-2, genome : ACaacc) were grown to maturity. Two concentrations of MES (5 or 10 mM) were included in Hoagland 1 nutrient solution. Alternatively, resin beads were incorporated into the 2 vermiculite : 1 perlite (v/v) growth medium at 6% or 12% of total substrate volume. Both strategies stabilized pH without toxic side effects on plants. Average seed yield rates for all four pH stabilization treatments (13.3 to 16.9 g m-2 day-1) were about double that of the control (8.2 g m-2 day-1), for which there was no attempt to buffer substrate pH. Both the highest canopy seed yield rate (16.9 g m-2 day-1) and the highest shoot harvest index (19.5%) occurred with the 6% resin bead treatment, even though the 10 mM MES and 12% bead treatments maintained pH within the narrowest limits. The pH stabilization methods tested did not significantly affect seed oil and protein contents.

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Alkanesulfonic AcidsBrassicaBuffersCapillary ActionCation Exchange ResinsCulture MediaHydrogen-Ion ConcentrationHydroponicsMorpholinesPlant OilsPlant ProteinsPlant RootsSeedsNASA Discipline Life Support SystemsNASA Discipline Number 93-10NASA Program NSCORTNon-NASA CenterJournal ArticleResearch Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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J Frick, C A Mitchell. 1993. Stabilization of pH in solid-matrix hydroponic systems.. https://pubmed.ncbi.nlm.nih.gov/11537992/

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