NaCl和Na2SO4盐胁迫对波斯菊种子萌发的影响

摘要

Seeds of Cosmos bipinnatus are used as experimental materials, different concentrations of NaCl and Na2SO4 solution were made as treatments, respectively. Germination indices, and physiological index of seedlings were measured to study effects of NaCl and Na2SO4 stress on seed germination of Cosmos bipinnatus. Results showed that the germination energy, germination rate, the growth indices and SOD activity of seedling al decreased while MDA content of seedling increased with the increasing of concentrations of NaCl and Na2SO4 solution. Suitable concentration range of Cosmos bipinnatus under NaCl and Na2SO4 stress was 0.11 and 0.08 mol·L-1, the half-lethal concentration was 0.67 and 0.13 mol·L-1, and the fatal concentration was 1.35 and 0.23 mol·L-1, respectively. Therefore, NaCl and Na2SO4 salt stress had inhibitory effects on seed germination of Cosmos bipinnatus, and inhibitory effect of Na2SO4 on seed germination of Cosmos bipinnatus was stronger than NaCl under the same concentration .%以波斯菊种子为试验材料，在种子萌发过程中选用不同浓度NaCl和Na2SO4进行胁迫，测定盐胁迫下种子萌发指标和幼苗生理指标，探讨NaCl和Na2SO4盐胁迫对波斯菊种子萌发的影响。结果表明，随着NaCl和Na2SO4浓度的增加，波斯菊种子发芽率、发芽势和幼苗芽长、根长、鲜重、侧根数及SOD活性均呈下降趋势，而MDA含量逐渐增加。波斯菊种子萌发时对两种盐的耐盐适宜范围为NaCl 0.11 mol·L-1、Na2SO40.08 mol·L-1，耐盐半致死浓度为NaCl 0.67 mol·L-1、Na2SO40.13 mol·L-1，耐盐极限值为NaCl 1.35 mol·L-1、Na2SO40.23 mol·L-1。表明，NaCl和Na2SO4盐胁迫抑制波斯菊种子萌发及幼苗生长，且相同浓度下，Na2SO4抑制作用强于NaCl。