摘要
采用现场采集植物样品、室内溶液培养方法,研究了铅胁迫对铅富集生态型和非富集生态型东南景天叶片干重,叶绿素含量和叶片超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性以及丙二醛(MDA)含量的影响。结果表明,即使在480mg·L-1处理水平,富集生态型东南景天的叶片干重,叶绿素a+b,叶绿素a,叶绿素b和MDA水平与对照相比均无显著差别。非富集生态型的叶绿素a+b,叶绿素a,叶绿素b和MDA水平明显低于对照。两种生态型的SOD、POD、CAT活性在铅胁迫下均比对照有所增加,但富集生态型增加的程度低于非富集生态型。由此推测,在相同铅胁迫下,富集生态型东南景天叶片细胞的受害程度小于非富集生态型。富集生态型叶片铅含量与叶片POD、CAT活性变化呈显著正相关;而非富集生态型叶片铅含量与叶片干重、叶绿素含量变化呈显著负相关,与MDA含量和SOD活性变化呈显著正相关。
The Pb accumulating ecotype and non- accumualting ecotype of Sedum.Alfredii (Hance) were exposed to a range of (0～ 480 mg· L- 1) Pb concentrations in solutions under laboratory conditions to determine lead accumulation patterns in leaf tissue, effects on chlorophyll contents, melondialodehyde (MDA) contents and activities of dismutase (SOD), peroxidase (POD) and catalase (CAT). We found that in the leaf of non- accumulating ecotype, lead was accumulated linearly with Pb concentration in solution. As for the accumulating ecotype, Pb concentrations in leaf increased at low Pb treatments, parking at 160 mg· L- 1 treatment, and then decreased at the treatment with 480 mg· L- 1. Under Pb treatments, the decrease of chlorophyll content and leaf dry weight were only observed in the leaves of the non- accumulating ecotype, and the increase of the MDA content and the activities of SOD, POD and CAT in the leaves of the non- accumulating ecotype were higher than those of the accumulating ecotype. Positive linear relationships between POD activity and Pb concentrations in leaf, and between CAT activity and Pb concentrations in leaf were found in the accumulating ecotype. Significant linear increase in the MDA content and SOD activity with increasing leaf Pb concentrations, and significant linear decrease in leaf dry weight and chlorophyll contents with increasing Pb concentrations in leaf were observed in the non- accumulating ecotype.
出处
《农业环境科学学报》
CAS
CSCD
北大核心
2003年第3期274-278,共5页
Journal of Agro-Environment Science
基金
国家教育部重点基金项目资助(02180)
