Effects of exogenous calcium on the seed germination and seedling ions distribution of Trifolium repens under salt-stress

Taking experiments of germination and seedling growth of Trifolium repens under salt stress under the conditions of phytotron, the effects of supplementary CaCl 2 (0.5,1,2,4,8g/L) on germination and seedling growth at NaCl concentration (6g/L) stress, especially on the distribution of Na+, K+, Ca2+, Mg2+ in roots and shoots were studied. The results show that proper supplementary CaCl 2 (2g/L)can improve seeds germination and seedling growth significantly under 6g/L NaCl, but high level CaCl 2 (8g/L) inhibit seeds germination, supplementary 2g/L CaCl2 can stimulate growth of seedling, and increase shoot / root ratio, and maintain ion balance (the K+, Ca2+ concentration in the seeding increase and Na+ concentration decrease significantly), and improved salt tolerance, but 8g/L CaCl 2 results in adverse effects to the germination and seedling growth, also disturbs the ion homeostasis.