Effects of NaCl on Growth, Dry Matter and Ion Accumulation in Forage Crop Astragalus Adsurgens Seedlings

Abstract

Astragalus adsurgens pall. is a pasture perennial legume widely planted in northern China. A greenhouse experiment was carried out to investigate the effects of salinity on growth, nutrient, organic solute accumulation, pigments and chlorophyll a fluorescence of A. adsurgens seedlings. Seedlings cultured for 20 d under NaCl solutions were harvested and growth, dry matter and ion accumulation were analyzed. The growth parameters except root length were reduced after NaCl treatment. Nitrogen, phosphorus and potassium contents decreased under NaCl salinity stress. Shoot water content decreased with increasing NaCl concentration whereas Na+, Cl-, proline and soluble sugar in shoot increased with increasing NaCl concentration. Moderate salinity (0.3 M NaCl or below) did not inhibit chlorophyll synthesis or photosystem II (PSII) function by inactivation of PSII reaction centers. High salinity (0.5 M NaCl) markedly disturbed chlorophyll synthesis and inhibits PSII activity. A. adsurgens is a salinity-sensitive plant species.