Responses Of Alocasia Macrorrhiza To Different Water Stresses And Pollutants Exposures

At present, heavy metal pollution and water eutrophication problem has beening obstruction to China's economic. In contaminated soil and eutrophic water treatment, bioremediation has been increasing concerned. In this paper, Alocasia macrorrhiza was studied as a soil heavy metal pollution and water eutrophication plant. The main results are shown as follows:1. A pot experiment was carried out by growing 5 different strains of A. macrorrhiza under Low-Cd-Pb ( Cd = 0.39 mg kg^-1,Pb = 59.26 mg kg^-1 ) , Middle-Cd-Pb(Cd =5.42 mg kg^-1,Pb =583.60 mg kg^-1)and High-Cd-Pb(Cd =10.60 mg kg^-1,Pb =1202.53 mg kg^-1)exposures. Biomass of A. macrorrhiza under the 3 treatments were no significant differences. Accumulation of Cd and Pb is mainly affected by soil Cd, Pb concentration. Cd, Pb concentration of A. macrorrhiza increased as soil Cd, Pb concentration increased. Cd, Pb concentration of the rhizome and root were significantly higher than of shoot. Cd content of the rhizome and root reached 133.556 mg kg^-1 averagely,and Pb content reached 427.283 mg kg^-1 averagely. A. macrorrhiza has the potential to be a bioremediation plant.2. A sand culture experiment was carried out by growing A. macrorrhiza in LevelⅢ,LevelⅣand LevelⅤwater. The results showed that A. macrorrhiza could remove NH₃-N and TN effectively. After 7-day treatment, the removal rate of NH₃-N and TN reached over 97% and 88.5% respectively. The remove of TP was slightly worse, but the removal rate of TP could still reached 39.5%-67.8% in LevelⅣand LevelⅤwater. A. macrorrhiza is a plant that suitable for water purification.3. A pot experiment was carried out by growing A. macrorrhiza under control, drought stress, submerged stress and semi-submerged stress. RWC, RPP (membrane permeability), MDA, Chl a + b, Chl a / b, Fv / Fm, SS (soluble sugar), Pro(Proline) was measurement and analysis. The results showed that A. macrorrhiza could survive a short period of time under drought stress, but a longer period of time under submerged stress. And it could grow pretty well under semi-submerged stress with no symptom of being poisoned.