EFFECTS OF LEAD POLLUTION ON GERMINATION AND SEEDLING GROWTH OF TURFGRASS, CYNODON DACTYLON

Lead (Pb) pollution in soils often triggers a catastrophic impact on crop growth and creates concerns related to food safety while seriously affecting agricultural production. Turfgrass, which produces a large amount of biomass, has been widely grown as a heavy metal sink. The present study evaluates the germination and seedling growth responses of turfgrass, Cynodon dactylon, to different levels of Pb(NO3)2. The results indicated that 50-300 mg/kg of Pb(NO3)2 did not significantly influence germination. The germination percentage and index gradually decreased with an increase of Pb(NO3)2 from 300-1000 mg/kg. The growth of root, shoot, as well as contents of chlorophyll a and b decreased with increasing Pb concentrations. The contents of soluble sugar, proline, MDA, SOD, and POD activity increased with an increase of Pb(NO3)2. When the concentration of Pb was below 500 mg/kg, the activity of CAT would first increase and then decrease. The high tolerance and accumulation of Pb by C. dactylon make it a useful accumulator of Pb. Therefore, this species will be useful in the phytoremediation and revegetation of Pb contaminated soil.