中文摘要：

通过桶栽试验，研究了盐分胁迫对向日葵生育期、株高、花盘直径的影响，并用Mass-Hoffman分段函数以及“S”型非线性耐盐函数拟舍了向日葵产量和盐分的关系。结果表明，盐分延长了萌发期和苗期时间，向日葵营养生长时间过长，生殖生长时间受到抑制。盐分影响向日葵株高、花盘直径总生长量及其在各生育期的分配比例，盐分越高，株高蕾期增长量所占比例越大，花盘直径成熟期增长量所占比例越小，不利于产量的形成。中盐区向日葵产量对盐分最敏感，低盐区次之，高盐区最不敏感。“S”型非线性耐盐函数可以很好的描述盐分与产量之间的关系。

英文摘要：

Pot experiments were conducted to study the effects of salt stress on growth stages, crop height and flower disc diameter, and the threshold-slope model of Maas-Hoffman and the alternative S-shaped sa- linity response model were used to describe sunflower yield response to soil salinity. The results showed that the germinating stage and seedling stage were lengthed under soil salt stress, and the generative growth was restrained. Both of the total increment and the proportion of sunflower height and flower disc in different growth stages were influenced by salt stress. The higher soil salt content, the higher increment proportion of height in bud stage and the smaller increment proportion of flower disc in mature stage, which was harmful to the yield. Yield of sunflower decreased the most severely under moderate salt stress, followed by low soil salt content and high soil salt content. The S-shaped salinity response model could de- scribe well the relationship between soil salinity and yield.