Noccaea caerulescens, a hyperaccumulator, and Lupinus albus, an excluder, were grown in three soils of differing pH: an acidic soil, a neutral soil (both contaminated mainly by Cu, Zn and As) and a control soil. Then, plant stress indicators were measured.
As expected, N.?caerulescens accumulated higher levels of Zn and Cd in shoots than L.?albus, this effect being stronger in the acid soil, reflecting greater TE solubility in this soil. However, the shoot concentrations of Mn were higher in L.?albus than in N.?caerulescens, while the As concentration was similar in the two species. In L.?albus, the phenolic content and lipid peroxidation were related with the Cu concentration, whereas the Zn and Cd concentrations in N.?caerulescens were more closely related to glutathione content and lipid peroxidation. Interestingly, phytochelatins were only found in L.?albus grown in polluted soils. Hence, the two species differed with respect to the TEs which provoked stress and the biochemical indicators of the stress, there being a close relationship between the accumulation of TEs and their associated stress indicators in the different plant organs.