摘要
研究了中国北方地区常用的塑料地膜对小麦Triticum aestivum L.种子发芽率,芽长根长及幼苗抗氧化酶系的影响以探明塑料地膜的毒性。结果显示500~2 500 mg.kg-1两种质量分数的塑料地膜处理对小麦种子的发芽率几乎不产生影响,在高质量分数（≥5 000 mg.kg-1）处理下小麦的发芽率有所下降。500~5 000 mg.kg-1的塑料地膜能促进小麦叶和根的伸长,但在高质量分数情况下则显著抑制了根和芽的延伸,其中15 000 mg.kg-1添加量下,叶和根的抑制率分别达到了16.70%和15.07%。小麦根系抗氧化酶活性对两种塑料地膜的敏感程度大于叶片。在高质量分数条件下,根系中超氧化物歧化酶（SOD）活性随暴露时间的延长明显受到了抑制。在经地膜1和地膜2处理后,小麦叶片中过氧化物酶（POD）及过氧化氢酶（CAT）活性在不同暴露时间和不同质量分数下没有显著差异,但地膜1处理后的小麦根系中的POD随暴露时间的延长呈先降低后增加的趋势,而CAT活性变化不大。地膜2处理后的小麦根系中的POD和CAT活性随暴露时间的延长而降低。结果表明,高质量分数塑料地膜的处理会对小麦早期幼苗的抗氧化酶系统产生毒害作用。
Plastic film mulch has been widely used in agricultural production in the North of China and the effects of plastic film mulch on seed germination,root and shoot length were investigated in this study.The activities of antioxidant enzyme were investigated to elucidate the toxicity of plastic film mulch.The results showed that 500~2500 mg·kg-1 of plastic film mulch had scarcely effects on seed germination and the seed germination decreased at the higher concentrations.At the addition of 15000 mg·kg-1,the elongation inhibition rate of the leaves and roots reached 16.70% and 15.07%.Plastic film mulch of 500~5000 mg·kg-1 stimulated the growth of root and shoot.However,these were decreased significantly at the highest concentration.The activities of antioxidant enzyme were sensitive in root than in shoot.The SOD activity was restrained distinctly in root with the prolongation of exposure time.With the treatment of plastic film mulch 1 and 2,the POD and SOD activities in leaves were similar to the control and,no significant differences were observed under different concentrations at exposure time.The POD activity increased with the treatment time and then decreased with further treatment by plastic film mulch 1,In comparison,the change of CAT activity is insignificant.Plastic film mulch 1 treatment decreased the POD and CAT activity with the prolongation of exposure time.The results demonstrate that high concentrations of plastic film mulch had toxicity on wheat in accordance with variations in these physiological indexes of wheat.
出处
《生态环境学报》
CSCD
北大核心
2010年第11期2702-2707,共6页
Ecology and Environmental Sciences
基金
国家科技支撑计划项目(2007BAC16B03)
关键词
塑料地膜
种子发芽及根伸长
抗氧化酶
小麦
plastic film
seed germination and root elongation
antioxidant enzyme
wheat
