Einfluß von NaCI-Salinität auf die CO2-Assimilation und auf den Einbau von 14C in verschiedene Inhaltsstoffe bei jungem Sommerweizen

Effect of NaCI salinity on CO₂ assimilation and incorporation of ¹⁴C in various chemical fractions of young wheat plants The effect of an increasing NaCI salinity on CO₂ assimilation and on the distribution of ¹⁴C in various chemical fractions of young wheat plants was studied. Increasing salinity restricted growth and in particular ¹⁴CO₂ assimilation being measured at the end of the experimental period. Correspondingly the amounts of ¹⁴C found in the various chemical fractions (amino acids, organic anions, carbohydrates, proteins, lipids, insoluble residue) were decreased with an increase in salinity. The relative distribution of ¹⁴C in the chemical fractions also was affected by salinity. At low salinity level a relatively low ¹⁴C concentration was found in the low molecular fractions, while the high molecular fractions showed a relatively high ¹⁴C concentration. At high salinity level this tendency was only weakly evident. Increasing salinity had no major impact on the nutrient concentrations (N, P, K, Ca, Mg) in the shoots, whereas the concentration of Na and especially of CI was remarkably raised. It is assumed that this excessive Na and CI concentrations in the shoots are resulting in the yield depression.