Abstract: The effects of silicon (Si) on physiological characteristics of Lycium ruthenicum seedlings under salt stress were studied by investigating leaf chlorophyll, membrane permeability, malondialdehyde (MDA), proline and soluble sugar content. Results showed that chlorophyll, membrane permeability, MDA, proline and soluble sugar content increased significantly compared with control under salt stress. Chlorophyll content and chlorophyll a/chlorophyll b increased significantly, whereas membrane permeability, MDA, proline and soluble sugar content decreased when silicon concentration was above 1 mmol·L^-1. Several physiological indices in silicon treatments were less than those in salt stress treatments with increased treatment. The change tendency of chlorophyll, chlorophyll a/chlorophyll b, MDA and proline content of Lycium ruthenicum seedlings in silicon concentration 4 and 8 mmol·L^-1 treatments was contrary to that in salt stress treatments showing that the appropriate concentration of exogenous silicon can alleviate the salt injury of Lycium ruthencium seedling.

Key words: Silicon, Salt stress, Lycium ruthenicum, Alleviation effect

摘要： 以盐生植物黑果枸杞(Lycium ruthenicum)幼苗为材料,NaCl胁迫下设置不同硅浓度处理,并在处理后第7 d和第14 d,对叶片叶绿素、质膜相对透性、丙二醛(MDA)、脯氨酸(Pro)和可溶性糖共5种生理指标进行测定,以探讨外源硅对盐胁迫下黑果枸杞生理特性的影响。结果表明:在盐胁迫下,黑果枸杞叶片叶绿素总量、质膜相对透性、MDA、脯氨酸和可溶性糖含量均显著增加;硅浓度大于1 mmol·L^-1时可显著增加盐胁迫下的叶绿素总量和叶绿素a/b,并降低质膜相对透性、MDA、脯氨酸和可溶性糖含量;随处理时间的延长,硅处理下5种生理指标的降幅或增幅均小于盐胁迫处理,而当硅浓度为4和8 mmol·L^-1时,叶绿素总量、叶绿素a/b、MDA和脯氨酸含量的变化趋势与盐胁迫处理的相反,可见适宜浓度的硅可缓解盐胁迫对黑果枸杞幼苗的伤害。

关键词: 硅, 盐胁迫, 黑果枸杞, 缓解效应