Two-dimensional electrophoresis of soluble leaf proteins, isolated from two wheat species (Triticum durum and Triticum aestivum) differing in sensitivity towards NaCl

Plants of two wheat species (Triticum aestivum cv. Tanit and T. durum cv. B en Bachir), differing in their sensitivity to NaCl were cultivated in the p resence or absence of 100 mM NaCl for 21 days. Soluble proteins extracted f rom leaves were analyzed by two-dimensional electrophoresis in order to det ect NaCl-induced changes in the polypeptide patterns. In all, 500 spots wer e detected. Results showed species-dependent differences. The greatest alte rations in the polypeptide profiles following salt stress were found in the most sensitive cultivar: among the 12 spots (molecular mass, 15-31 kDa) sp ecifically considered in the acidic region of the gel, 11 declined, even di sappeared in the NaCl-sensitive leaf profiles, while in the tolerant specie s only five spots were affected by the salt treatment and five remained unt ouched; moreover in the latter, two new polypeptides were shown to be induc ed by NaCl.