Inducing salt tolerance in maize (Zea mays L.) through seed priming with chloride salts: Growth and ion transport at early growth stages

Abstract

The study was conducted to determine whether salt tolerance could be induced in maize at germination stage by soaking of seeds for 8 h in distilled water or in 200 meq·L−1 of NaCl, KCl, CaCl2·2H2O. Both primed and un-primed seeds were subjected for 14 days to 0, 100 or 200 mol·m−3 NaCl under controlled conditions. Although all priming agents were effective in alleviating adverse effects of salt stress on maize at germination stage, CaCl2·2H2O proved to be more effective since the seeds primed with this salt had significantly higher final germination, rate of germination and fresh and dry weights of plumules and radicles than those treated with other salts or distilled water. Concentration of Na+, K+ and Ca2+ increased significantly in all parts of germinating seeds of maize seeds primed with NaCl, KCl, or CaCl2·2H2O, respectively. In addition, seeds primed with CaCl2·2H2O were the highest in Cl− accumulation in all parts of the germinating seeds, followed by seeds treated with NaCl and KCl. Most of the Ca2+ was retained in seeds and mesocotyl, because of which, transport of this ion to plumules and radicles was low.