Effects of Cadmium Stress on Physiological and Enrichment Characteristics of Cosmos sulphureus
In order to provide phytoremediation materials with landscape restorative properties for areas contaminated by soil cadmium(Cd),the pot experiment was conducted to study the effects of different mass concentrations of Cd(0,0.3,3,30,60,120,180 mg/kg)on physiological and enrichment characteristics of Cosmos sulphureus plants.The results were as follows.At 15 days of stress,with the increase of cadmium concentration,the soluble protein,chlorophyll a,chlorophyll b and carotenoid contents and SOD activity in leaves of C.sulphureus showed the tendency of firstly increasing and then decreasing,the MDA content de-creased gradually,and the POD activity decreased first and then increased;ETR,qP and Tr reached the highest values at 0.3 mg/kg of cadmium,Pn and Gs reached the highest values at 3 mg/kg of cadmium,NPQ reached the lowest value at 30 mg/kg of cadmium,Fv/Fm reached the highest value at 60 mg/kg of cadmium,and Fo reached the lowest value at 180 mg/kg of cadmium.At 30 days of stress,soluble protein content and SOD activity increased first then decreased,MDA content increased first then decreased and then increased,and POD activity decreased first then increased and then decreased;chlorophyll a,chlorophyll b and carote-noid contents decreased first and then increased;Fv/Fm reached the highest value at 0.3 mg/kg of cadmium,NPQ reached the highest value while Tr,Pn and Gs dropped to the lowest values at 3 mg/kg of cadmium;qP reached the highest level and Fv/Fm reached the lowest level at 30 mg/kg of cadmium;Pn and Gs reached the highest values but Fo and NPQ dropped to the lowest values at 60 mg/kg of cadmium;Ci decreased to the lowest value at 120 mg/kg of cadmium,and Tr and ETR were the highest at 180 mg/kg of cadmium.When Cd concentration was<180 mg/kg,the Cd content in the organs showed stems>roots>leaves,and showed roots>stems>leaves when Cd concentration was≥180 mg/kg.When the cadmium concentration was≥120 mg/kg,the cadmium content in roots,stems and aboveground parts of C.sulphureus exceeded the critical val-ue of cadmium super-enriched plants.In conclusion,C.sulphureus had excellent tolerance to high concentra-tion cadmium stress and strong cadmium enrichment ability,which could be used as a phytoremediation mate-rial with landscape restoration.
万方数据
维普
