Metales pesados en las semillas de álamo blanco

White poplar (Populus alba) is a tree species which accumulates Cd and Zn in leaves and branches, as previous studies in the Guadiamar Green Corridor (Seville) have demonstrated. However, whether heavy metals are also accumulated in seeds was not known. This aspect is very relevant because the germination and seedling growth can be negatively affected.

Researchers from the IRNAS, CSIC, led by Paula Madejón, in collaboration with the National Accelerator Centre of Seville, have studied in detail seeds collected from white poplar trees growing in the area contaminated by heavy metals after the mine accident of Aznalcóllar. They have been compared with seeds from other poplar trees growing in non-contaminated areas, used as control.

It has been demonstrated that white poplars accumulate Cd and Zn also in the seeds, indicating that this species lacks of effective barriers to impede the entrance of heavy metals into the reproductive organs. However, those high concentrations of Cd and Zn in seeds did not affect negatively their germination and the seedling development. These results support that white poplars are tolerant to contaminated soils, that accumulate Cd and Zn in leaves and also in seeds, but the germination and seedling growth are not negatively affected.

This study has been published in the journal Environmental Monitoring and Assessment

Madejón, P, Cantos, M, Jiménez-Ramos, MC, Marañón, T, Murillo, JM. 2015. Effects of soil contamination by trace elements on white poplar progeny: seed germination and seedling vigour. Environmental Monitoring and Assessment 187: 663.