Effect of exogenous Calcium on seed germination and seedling physiological characteristics of Lycium ruthenium

OBJECTIVE: In order to get the method for improving the salt resistance of Lycium ruthenium seeds and seedlings under NaCl stress, the seed germination and physiological characteristics of L. ruthenium seedlings was studied. METHOD: Several physiological indexes of L. ruthenium seeds under NaCl stress, such as the germination rate (Gr), germination vigor (Gv), germination index (Gi), vigor index (Vi), and relative salt damage rate were measured. Other indexes of the seedlings like relative water contents (RWC) , chlorophyll contents, soluble protein contents, electrolyte leakage, the contents of malondialdehyde (MDA), and peroxidase (POD) were also measured. RESULT: NaCl at lower concentration could promote the seed germination but inhibit the seed germination at higher concentration. After the treatment by CaCl2 at the different concentrations, all germination indexes were increased. With the increase of salt concentration, the relative water contents and the contents of chlorophyll were decreased, the content of MDA and electrolyte leakage were increased. The change trend of POD activity showed the first increase and then decrease with the increase of salt concentration, which was similar to that of the soluble protein. After the treatment by CaCl2, relative water contents, chlorophyll and POD activities were decreased more slowly, and also electrolyte leakage and MDA contents increased slowly. CONCLUSION: The CaCl2 could significantly alleviate the damages to the seeds and seedlings of L. ruthenium under NaCl stress, and promote the salt resistance to the seeds and seedlings of L. ruthenium.