Die Bodenkultur - Journal for Land Management, Food and Environment

S. M. ULLAH, G. SOJA and M. H. GERZABEK:

Ion uptake, osmoregulation and plant-water relations in faba beans (Vicia faba L.) under salt stress

Summary

In pot experiments, the effects of irrigation with artificial seawater on faba beans were investigated. The sum of the salt concentration was 0, 20, 40 and 60 mM (NaCl: MgCI2 : MgS04=2: 1 : 1 on molar basis). Salt stresses increased the concentrations of sodium, magnesium and chloride ions in the plants. Sodium reduced the uptake of potassium due to ion antagonism. Decreased iron concentrations induced chlorosis. Chloride antagonized the uptake of nitrate. Phosphate increased significantly in response to ion balance. Significant increases in glucose, fructose, in some cases sucrose, proline and calcium contents in faba beans showed some tendency of this crop to adjust osmotically against salt stress, Salinity reduced leaf water potential (ψt) as well as osmotic potential (ψs) Leaf water potential (ψt) decreased from - 9 x 105 Pa under control conditions to - 14 X 105 Pa under severe salt stress, Grain as well as straw yields of Faba beans were decreased significantly by artificial salinity. At the highest stress level (60 mM salt) grain yields were reduced by 85 %, while straw yields decreased by 43 % at 60 mM. Key-words: salt stress, seawater salinity, osmotic adjustment, leaf water potential, osmotic potential.