Salinity effect and seed priming treatments on the germination of Suaeda salsa in the tidal marsh of the Yellow River estuary

Abstract

The effects of salinity and seed priming treatments (hydropriming, water, KNO₃ and KH₂PO₃) on the germination of the euhalophyte Suaeda salsa in intertidal zone of the Yellow River estuary were investigated. Results show that the seed germination percentage decreased with increasing NaCl concentration, and at the high NaCl level (800 mM), the lowest germination percentage was recorded. At the low NaCl levels, the highest germination rate was observed on day two and the seedling length was promoted slightly. In contrast, the germination delayed and the seedling length decreased at the high salinity. According to the survival functions, we also found that, at the low salinity, the seeds germinated quickly at the initial days and then the germination rate decreased, while few seeds germinated at the initial days at the high salinity. From the results of germination percentage and seedling length, we found that the effect of Yellow river water on germination was similar to the 400 mM NaCl. For priming treatments, the hydropriming has no promotion to the seeds germination, but it promoted the seedling growth at the river water and 400 mM NaCl. Seeds primed with KNO₃ could improve the germination at the low salinity, while priming with KH₂PO₄ could improve the seedling growth at the high salinity, indicating that seed priming with proper nutrient (N, P) solutions could improve the germination or seedling growth as the nutrient (N, P) availability in the soil of S. salsa marsh was very limited.

Keywords: Suaeda salsa, germination, salinity, priming, Yellow River estuary