Abstract: Aimed to understand the germination strategies of Suaeda salsa under different environmental stress in the Yellow River Delta, an indoor germination test was conducted, and the seedling’s Na⁺ and K⁺ contents were determined at different temperature, salinity, and alkalinity, and in seawater solution. The thermal time and base temperature for the seed germination were 24.57 ℃·d and 0.62 ℃, respectively, and the optimal temperature was 20 ℃-35 ℃. The germination percentage was high at 5 ℃-40 ℃, and the germination rate increased significantly when the temperature increased from 5 ℃ to 35 ℃. The germination percentage was higher than 50% in 500 mmol·L^-1 of NaCl, and about 38% in 100% seawater. After seeds transferred from high concentration NaCl solutions to distilled water, the un-germinated seeds  could germinate well, which indicated that the un-germinated seeds could remain active in high salt habitats. With the increasing concentration of NaCl in solution, the seedling’s Na⁺ content increased significantly, while the K⁺ content had less change. In 200 and 300 mmol·L^-1 of NaHCO₃, the seedling’s Na⁺ and K⁺ contents were significantly lower than those in 100 mmol·L^-1 of NaHCO₃, indicating that high alkalinity stress affected the ion accumulation in S. salsa seedling’s significantly. With increasing seawater concentration, the seedling’s Na⁺ and K⁺ content also had significant increase. Therefore, the wide temperature-adaptation and high salt-tolerance for seed germination, the high seed vigor under high salt stress, and the high salt ion accumulation in seedling could be the main germination strategies of S. salsa adapting to the complicated environments in saline-alkaline wetlands of the Yellow River Delta.

Key words: Forest soil, Polyphenols, Ecological regulation, Secondary mestabolite