Résumé:
Lead pollution has become a real problem threatening our ecosystems, with damaging effects on plant production and biodiversity. The comparative study consists of studying the biometric and metabolic behavior of the radish plant (Raphanus sativus L.) to approximate the impact of heavy metals (lead).
Radish plants (Raphanus sativus L.) are stressed by lead in the form of lead nitrate solution (PbNO3) at different concentrations (0, 100, 200, 500 and 1000 ppm), (0.250, 500 and 1000 ppm) ), and (0.500, 1000 and 2000 ppm). Metallic stress is applied for fifteen days, after 45 days of development of (Raphanus sativus L.).
Biometric analysis after exposure to lead showed inhibition of the upper part of the plant, the mass of fresh matter from different radish organs compared to controls. Physiological analysis showed a decrease in the content of foliar chlorophyll pigments (chlorophyll a, b and total) and in the carotenoids content of radish plants exposed to lead at different concentrations, compared to the control.
The species Raphanus sativus L. has protective mechanisms that allow it to tolerate this excess lead. This plant can be used in a soil depollution system because it has particular properties of natural resistance to numerous abiotic constraints.