盐胁迫对雪菊种子萌发的影响

以雪菊(Coreopsis tinctoria Nutt.)种子为试验材料，研究盐胁迫对雪菊种子萌发的影响。用不同浓度的NaCl、Na₂SO₄以及混合盐NaCl:Na₂SO₄:Na₂CO₃=2:7:1（质量比）处理雪菊种子。结果表明：盐胁迫使雪菊种子的发芽指数、发芽势和发芽率明显降低，且随着盐浓度的增加,抑制作用增强；3种盐对雪菊种子萌发的抑制作用强度依次为：混合盐>NaCl>Na₂SO₄；雪菊种子耐盐适宜范围为NaCl 0.78%、Na₂SO₄ 0.84%、混合盐0.15%；耐盐半致死浓度为NaCl 1.34%、Na₂SO₄ 1.41%、混合盐0.89%；耐盐极限浓度为 NaCl 2.23%、Na₂SO₄ 2.31%、混合盐2.08%。盐胁迫解除后雪菊种子仍具有较高的萌发率。

Effects of Salt Stress on Seeds Germination of Coreopsis tinctoria.

The effects of NaCl, Na₂SO₄ and 2:7:1 (NaCl+Na₂SO₄+Na₂CO₃) under different concentration on the seeds germination of Coreopsis tinctoria was studied. The results showed that the germination index, germination potential and germination rate of Coreopsis tinctoria seeds decreased obviously under the stress of test salts; moreover, the inhibition was strengthened with the increase in the concentrations of salts stress. Compared the inhibition showed that mixed salt>NaCl>Na₂SO₄. The suitable salt concentration for Coreopsis tinctoria seed germination was 0.78% NaCl, 0.84% Na₂SO₄ and 0.15% mixed salt; the half lethal concentration and fatal concentration of NaCl, Na₂SO₄ and mixed salt was respectively 1.34%, 1.41%, 0.89% and 2.23%, 2.31%, 2.08%. Research also showed that after relieve the salt stress, seeds of Coreopsis tinctoria still had high germination rate.