关键词: 重金属, 递进胁迫, 黑麦草, 初期生长

Abstract: The experiment was conducted to investigate effects on initial growth of Lolium perenne L.under Cu²⁺, Zn²⁺, Cd²⁺ and Pb²⁺ stress. The results showed that four heavy metals didn’t inhibit seed germination significantly, especially Cu²⁺ and Zn²⁺ stress. At high concentrations, Cu²⁺ and Cd²⁺ stress decreased plant height, root length and aboveground biomass greatly, especially Cu²⁺ which inhibited root growth mostly. Compared with control, root length decreased by 85.48% at Cu²⁺ level of 300 mg·L^-1. High level of Cd²⁺ decreased chlorophyll content significantly. Compared with control, chlorophyll content decreased by 45.51% at Cd²⁺ level of 300 mg·L^-1. Chlorophyll contents increased at all stress levels of Cu²⁺ and Zn²⁺.From the process of progreessive stress, some heavy metal had positive effect on some growth index at low concentrations, but inhibited growth at high concentrations.

Key words: heavy metal, progressive stress, Lolium perenne L., initial growth