Effects of exogenous substances priming on Suaeda salsa seed germination under NaCl stress

This study investigated the effects of exogenous substances on seed germination and seedling growth of Suaeda salsa under NaCl stress, especially on seed germination enevgyl, germination rate, germination index, average germination speed, shoot and root length, and fresh weight of seedlings under the condition of phytotron. The exogenous substances consist of CaCl2 (5.0, 10.0, 20.0, 40.0 mmolL-1), salicylic acid (0.05, 0.5, 1.0, 2.0 mmolL-1) and betaine (5.0, 10.0, 20.0, 40.0 mmolL-1). The results showed that seed germination rate and speed significantly reduced and accompanied with severe inhibition of seedling growth under NaCl stress. Soaking with appropriate concentrations of exogenous substances could increase seed germination rate and speed significantly, promote seedling growth, it could alleviate salt injury to S.salsa. Under condition of 400 mmolL-1 NaCl stress, the optimal concentrations of CaCl2, salicylic acid and betaine were 20.0, 1.0 and 20.0 mmolL-1, respectively. Comparative analysis showed that integrated effects of betaine (20.0 mmolL-1) were the best.