Effect of lead stress on the chlorophyll fluorescence characteristics and antioxidative enzyme activities of Paspalum notatum
Paspalum notatum is considered one of the best grass species for controlling soil and water loss in south China.To test the feasibility of P.notatum as a restoration plant in mining wasteland,a pot experiment was undertaken with various concentrations of lead (Pb) (150,250,500,1000,1500 and 2500 mg/kg).Chlorophyll fluorescence,SPAD value,chlorophyll content,antioxidative enzyme activities and malondialdehyde content were measured to investigate physiological responses to Pb stress.The inhibitory effect of Pb stress on chlorophyll fluorescence was observed at the early stage (August),while significant promotion was found at later stages (September and October).Pb stress inhibited the SPAD value of chlorophyll and the chlorophyll content of P.notatum,but no significant differences from the control were observed.Pb stress promoted the activities of peroxidase and superoxide dismutase,but showed little effect on catalase activity.Malondialdehyde content of P.notatum increased under Pb stress,but there were no significant differences from the control at higher Pb concentrations.These results demonstrate that Pb stress inhibits some physiological characteristics in P.notatum and that the antioxidant system and chlorophyll fluorescence may play important roles in alleviating Pb toxicity.
国家科技期刊平台
NSTL
万方数据
维普
