EFFECT OF LEAD STRESS ON GROWTH AND ACCUMULATION RESPONSE OF PANICUM MAXIMUM IN TROPICAL SOIL

Using tropical plants in heavy metal-polluted environment restoration is a new bio-technique in ecological restoration research of tropical areas. Herein, we report a preliminary research to determine the growth and accumulation response of a typical tropical plant (Panicum maximum) on lead pollution. Results showed that Pb pollution in low concentration favored the height growth and dry weight increment of Panicum maximum, while in high concentration it disfavored. The addition of Pb increased all forms of Pb content in the soils, among which the residual forms exhibited a great reduction, while the Fe-Mn oxides and organic combined forms showed a great enhancement. The K-BCF value of roots of Panicum maximum ranged from 0.37 to 1.48. The concentration of lead in underground part was higher than that in aboveground part of Panicum maximum. So, this plant could still be a candidate for lead-contaminated soil reclamation.