Protection induced by external Ca2+ application on proline accumulation, ion balance, photosynthetic pigments, protein and ABA concentration of mustard seedlings (Sinapis alba L.) under salinity stress

Abstract

The effect of external Ca²⁺ application of different concentration to salinity-treated (100 mM NaCl) mustard plant (Sinapis alba L.) was investigated in relation to ion uptake, proline, chlorophyll a&b, protein and ABA concentrations. Salinity treatment (100 mM NaCl) led to significant decreases in Ca²⁺& K^uptake and Chl. a&b contents, accompanied by significant increases in Na+ uptake, proline and ABA concentrations. Salinity treatment also induced the appearance of new protein bands. The most effective concentrations of CaCl₂ treatment in protecting mustard plants against the adverse effect of NaCl salinity were 5, 10, and 15 mM CaCl₂. This could be attributed to the effect of CaCl₂ in decreasing ABA concentration, the synthesis of new polypeptides and increasing K⁺ and Ca²⁺ uptake.


KEY WORDS: salinity, CaCl₂, proline, protein, ABA.


Egyptian Journal of Biology Vol.4 2002: 14-22