Comparative study on the bioaccumulation of lead, cadmium and nickel and their toxic effects on the growth and enzyme defence strategies of a heavy metal accumulator, Hydrilla verticillata (L.f.) Royle

摘要: The current hydroponic experiment investigated differences in the uptake, physiological response and defence mechanisms of Hydrilla verticillata (L.f.) Royle to three representative toxic heavy metals. results revealed following: as an excellent metal accumulator, H. showed accumulation pattern Ni > Cd > Pb within experimental scope. Fourteen days (Ni Cd) 21 days (Pb) were time thresholds under same concentration toxicity, while 33.06 μM (Ni) 40 μM (Cd Pb) 21-day duration treatment, accumulate most amount Hence, Pb might be accumulated more if it expands concentration, for continuously increases throughout period. Reasons these uptake are that plant response, tolerance resistance vary different stress. First, biomass protein content both highest stress, indicating largest Second, antioxidant enzymes (SOD, CAT POD) Third, two other related resistance-causing (PPO PAL) was strongest at low Cd concentrations (0–20 μM) high stress levels (40 μM). Furthermore, is important enzyme combat stresses (average relevance: CAT(0.89) > POD(0.48) > SOD(0.42)), PAL than PPO (0.77) > PPO(0.72)). In conclusion, Pb-polluted water best treated with because latter’s potential strong capacity. These provide accurate, efficient economical reference phytoremediation.