Effects of Salt Stress on the Seed Germination and Seedling Growth of Erysimum amurense

PurposeTo study the salt tolerance characteristics of Erysimum amurense during the germination and seedling stages.

MethodDetermine the optimum germination temperature of E. amurense seeds at different temperatures (15, 20, 25 and 30 °C), and use different concentrations of NaCl, Na₂CO₃ and mixed salt (NaCl+Na₂CO₃) solution 0 (CK), 1, 2, 3, 4, 5, 6 g/L to simulate the salt stress environment at this temperature, determine the germination index at the germination stage and some morphological and physiological indicators, with the aid of regression equations to evaluate the salt tolerance.

Result(1) The optimal germination temperature of E. amurense seeds was 20 ℃, and the germination rate was 86.67%. (2) Under the optimal germination temperature, with the increase of salt mass concentration, the germination rate, germination potential, germination index and the fresh weight and dry weight of E. amurense under NaCl stress increased first and then decreased, while the root length, stem length, total length and water content showed a downward trend; the germination rate, germination potential, germination index and seedling root length, stem length, and total length of E. amurense under mixed salt stress showed a downward trend as a whole, while the fresh weight, dry weight, and water content increased firstly and then decreased; all measured indexes under Na₂CO₃ stress showed a downward trend. Three kinds of salt-stressed seeds all re-germinated after rewatering. (3) It could be seen from the regression equation that the critical concentration of E. amurense during germination and seedling stages was the highest under mixed salt stress, which are 7.26 and 5.48 g/L respectively, followed by NaCl, and Na₂CO₃ was the lowest.

ConclusionE. amurense has strong adaptability to mixed salt environment during the germination and seedling stages, and can be developed and utilized as salt-tolerant ornamental flowers.