Abstract
BACKGROUND: Copper is an important heavy metal pollutant, with strong toxicity and great harm, which is easy to accumulate in the plant body and is difficult for degradation. This paper adopts medium culture method, taking "Zheng Dan 958" maize seedlings as sample materials. With different copper ion concentration gradients for the simulation of metal copper stress on maize seedlings, it explored the effects on the membrane structure (POD activity, MDA content, membrane permeability) and root activity. RESULTS: POD activity increases dramatically when the copper concentration is over 10 μmol/L. MDA content increases sharply when the copper concentration is over 1000 μmol/L, showing a rising trend. Membrane permeability increases greatly when the copper concentration is over 100 μmol/L. Root activity decreases significantly when the copper concentration is 100 μmol/L, showing a clear downward trend. CONCLUSIONS: The copper concentration of 1000 μmol/L has exceeded the maize seedling tolerance to copper, and the activities of protective enzymes of maize seedlings are inhibited. Cell membrane lipid peroxidation has caused serious damage on the structure and function of membrane. Structure of root cells of maize seedling is also damaged, reducing the root activity, so the maize is irreversible hurt.