关键词: 莲藕, 重金属, Pb, Cd, 富集

Abstract: Effects of five combinations of two heavy metals，Pb and Cd，as pollutersat at both lower （100 mg · kg^-1 Pb + 0.2 mg · kg^-1 Cd），both higher（500 mg · kg^-1 Pb + 1.0 mg · kg^-1 Cd），Pb lower（100 mg · kg^-1）and Cd higher（1.0 mg · kg^-1），Pb higher（500 mg · kg^-1）and Cd lower（0.2 mg · kg^-1），and non-treated（the control）in big pots on their accumulation characteristics，physiological and biochemical indicators，produce qualities and yields in lotus root（Nelumbo nucifera Gaertn.）were analyzed. The result showed that there were a positive correlation between Pb and Cd accumulations in the various organs of louts root and the levels of Pb and Cd supplemented to the soil. And it occurred even in the lower concentrations，Pb and/or Cd still exceeded the national food hygienic standards. As a whole，the accumulation patterns showed the heavy metals are more in lotus leaf，swollen stem，petiole and creeping stem. The toxicity of Pb or Cd accumulated in lotus root displayed that total chlorophyll content decreased and the MDA content increased in lotus leaf than swollen stem，the soluble sugar declined and the soluble protein first increased and then decreased in the lotus leaf，however，there was no obvious change in swollen stem；The vitamin C increased at lower levels of both Pb and Cd，then declined，and a significant difference in higher level soil of Pb and Cd than the control. Also，we can see that the yield of swollen stem of lotus dropped down along with the concentration increases and had a significant difference in Pb + Cd higher soil than the control.

Key words: lotus root, heavy mental, Pb, Cd, accumulation