Screening of available local halophytes for salinity tolerance is of considerable economic value for the utilization of heavy salt-affected lands in coastal tidal-flat areas and other saline areas. In this study, the germination and seedling pot experiments on salt tolerance of eight halophytic species from Yellow River Delta, China, at seven NaCl concentrations (0, 50, 100, 150, 200, 250, and 300？mM), were conducted at both growth stages. Results showed that germination rate and germination index decreased with an increase in NaCl concentration. The higher germination rates were obtained from Tamarix chinensis and Suaeda salsa seeds exposed to 0~200？mM NaCl. At the seedling stage, the salt tolerances of eight halophytes were also different from each other. Tamarix chinensis had significantly greater fresh biomass and plant height in relative terms than the others in all salt treatments. The order of the relative growth yield in seedling was Tamarix chinensis > Suaeda salsa > Salicornia europaea > Limonium bicolor > Atriplex isatidea > Apocynum venetum > Phragmites australis > Sesbania cannabina. The comprehensive analysis showed that Tamarix chinensis had the highest tolerance to salt, followed by Suaeda salsa, and the salt tolerance of Sesbania cannabina was the lowest. 1. Introduction Soil salinization is one of the most serious impediments to agricultural production both in China and the other regions of the world [1, 2]. According to statistics, there is about of saline soil worldwide, and seven percent of the land surface and five percent of cultivated lands are affected by salinity [3, 4]. China has all kinds of saline soils with a total area of about . In the Yellow River Delta alone, there is approximately of seashore salinized tidal flat, including heavily salinized soil (soil salinity is over 0.6%) and saline-alkaline bare land with an area of . And this number continues to grow at a rate of per year due to a variety of natural and human activities [5–7]. On these saline lands, it is not suitable for growth of traditional crops because of extreme salinity and other adverse factors. If plant salt tolerance cannot be improved, then vast amounts of soils may be left uncultivated. This will severely threaten the national food security and biomass energy production. In recent years the development thinking of solonchak agriculture is brought up at home and abroad. Namely, salinized soils can be utilized through the transgenic technology or the breeding of salt-tolerant plants, which may successfully maintain a relatively reasonable yield and an
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