Changes in secondary metabolites in the halophytic putative crop species <i>Crithmum maritimum</i> L., <i>Triglochin maritima</i> L. and <i>Halimione portulacoides</i> (L.) Aellen as reaction to mild salinity

<div><p>It is assumed that salinity enhances the concentration of valuable metabolites in halophytes. The objective was to find a salt concentration and a point in time at which the yield for the valuable metabolites was maximal. Therefore, three different halophyte species were grown under different salinities and harvested over a period from shortly after stress induction up to three weeks. Various reaction patterns were found in the metabolite composition of the analyzed plant material. <i>Halimione portulacoides</i> showed a “short term response”, indicated by an increase in all metabolites analyzed after a few hours, whereas <i>Crithmum maritimum</i> showed a “long term response” through accumulation of proline starting after days. <i>Triglochin maritima</i> did not change in metabolite concentration, but like the other plant species the biomass was reduced by salinity. Generally, a higher production in secondary metabolites by higher salinity was outbalanced by a reduction in biomass production. Concentrations of analyzed antioxidants showed a similar reaction and correlated with each other.</p></div