Pb2+对甘肃纹党种子萌发和幼苗生理特性的影响

以甘肃道地中药材纹党(Codonopsis pilosula)为对象，通过室内培养试验，研究不同浓度10^-6、10^-5、10^-4、10^-3 mol/L Pb²⁺处理对纹党种子萌发、幼苗生长以及生理特性的影响，为探究Pb²⁺污染对纹党品质的影响提供依据。结果表明，Pb²⁺对纹党种子吸胀过程中相对吸水量的增加有抑制作用，随着Pb²⁺浓度的提高，党参种子的萌发率、萌发指数、幼苗生长及根尖微核和有丝分裂率变化，表现出先升高后降低的趋势；低浓度的Pb²⁺处理能够促进叶绿素的形成，高浓度则抑制叶绿素形成；可溶性糖、游离脯氨酸和丙二醛含量，随Pb²⁺浓度的升高而增加；Pb²⁺对SOD、POD和CAT活性有较强的抑制作用。可见，生物测定结果大多达到显著差异水平。

Effect of Pb2+ on Germination and Seedling Growth and Physioloyical Characters of Codonopsis pilosula of Gansu Chinese Herbal Medicine

The effect of the different concentration of Pb²⁺ (10^-6 mol/L,10^-5 mol/L,10^-4 mol/L,10^-3 mol/L ) on germination, seedling growth and physiological characters of Codonopsis pilosula of Gansu authentic Chinese herbal medicine was studied to provide the theoretical basis for the research on the relation of Pb²⁺ pollution with the quality of Codonopsis pilosula. The results showed that Pb²⁺ inhibited the water absorption during seed germination. The seed germination rate, germination index, primary embryonic root length and hypocotyl length, seedling growth and micronuclei and mitotic rate of root tips in the Codonopsis pilosula plants were firstly rose and then reduced with the increase of Pb²⁺ concentration. The low concentration of Pb²⁺ could stimulate the synthesis of chlorophyll, but restrained its synthesis on high concentration. The content of soluble sugar, malondialdehyde and free proline in the leaf was increased with the increment of Pb²⁺ concentration. The Pb²⁺ had strong inhibition to the activity of SOD, POD and CAT. Most of bioassay results reached the significant difference level.