张春平等

[目的]通過对黄连种子萌发及幼苗生理特性的研究，寻找提高黄连种子及幼苗在盐胁迫条件下抗性能力的途径。[方法]用100 mmol/L的NaCl模拟盐胁迫，在外源水杨酸（SA）处理后，对黄连种子的发芽势（Gv）、发芽率（Gr）、发芽指数（Gi）、活力指数（Vi），以及黄连幼苗叶片细胞质膜透性、O2-· 产生速率、H2O2含量、可溶性糖、可溶性蛋白、游离脯氨酸及丙二醛（MDA）含量、超氧化物歧化酶（SOD）、过氧化物酶（POD）、过氧化氢酶（CAT） 和抗坏血酸过氧化物酶（APX）活性进行测定。[结果] NaCl胁迫下的黄连种子萌发受到显著抑制，但在经过不同浓度的SA处理后，各萌发指标均有升高。试验结果表明，外源SA处理显著提高了黄连种子发芽势、发芽率、萌发指数和活力指数，明显提高了盐胁迫下黄连幼苗叶片可溶性糖、可溶性蛋白和脯氨酸含量，不同程度地提高了叶片超氧化物歧化酶（SOD）、过氧化物酶（POD）和过氧化氢酶（CAT）活性，显著降低了叶片丙二醛（MDA）含量、质膜透性、O2-· 产生速率及H2O2含量。[结论]外源SA通过提高黄连种子的萌发指数，提高渗透调节物质含量及抗氧化酶活性，降低细胞质膜氧化程度，有效地减缓NaCl 胁迫对黄连种子及幼苗产生的伤害，提高了种子及幼苗的抗盐能力。

关键词黄连；亚精胺；盐胁迫；种子萌发；生理特性

Abstract[Objective] In order to get the method of improving the salt resistance of seeds and seedlings for Coptis chinensis Franch. under NaCl stress， seed germination and physiological characteristics of C. chinensis seedlings were studied. [Method] Several physiological indexes of C. chinensis seeds and seedlings treated by exogenous salicylic acid under NaCl stress like the germination vigor， germination rate， germination index and vigor index were measured. And other indexes like the memberane permeability， H2O2 content， production rate of O2-， the contents of soluble surge， soluble protein， free proline， and malondialdehyde （MDA）， the activities of superoxide （SOD）， peroxidase （POD）， catalase （CAT）， and ascorbate peroxidase （APX） were also measured. The germination indexes of C. chinensis seeds under NaCl stress have an obvious inhibition. But after the treatment of salicylic acid， every germination indexes were all increased. [Result] The result showed that the treatment of exogenous salicylic acid obviously improved the germination vigor， germination rate， germination index and vigor index， increased the content of soluble sugars， free proline， and soluble protein， decreased the content of malondialdehyde （MDA）， H2O2 content， production rate of O2-· Meanwhile， the results also indicated that salicylic acid improve the activities of superoxide （SOD）， peroxidase （POD）， catalase （CAT）， and ascorbate peroxidase （APX）. [Conclusion] Exogenous salicylic acid with appropriate concentration could significantly alleviate the damages to the seeds and seedlings of C. chinensis under NaCl stress and promote the salt resistance of the seeds and seedlings through improve the germination indexes and antioxidase activities， decrease the memberane permeability and so on.

Key wordsCoptis chinensis Franch.； Spermidine； Salt stress； Seed germination； Physiological characteristics

黄连Coptis chinensis Franch.又名味连、川黄连、鸡爪连，为毛茛科黄连属多年生草本植物，三级渐危种[1]。野生黄连大多分布于四川、重庆、湖南、湖北、陕西、贵州省海拔1 200～1 700 m的山谷密林之中。黄连性寒、味苦，根茎入药，具有清热燥湿、泻火解毒等作用[2]，临床上还用于细菌性痢疾、局部化脓性感染、心律失常、胃炎及十二指肠溃疡等病的治疗[3]。……