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 CaCl₂(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 CaCl₂(2g/L)can improve seeds germination and seedling growth significantly under 6g/L NaCl, but high level CaCl₂(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 CaCl₂ results in adverse effects to the germination and seedling growth, also disturbs the ion homeostasis.