Accumulation and fractionation of rare earth elements are conserved traits in the Phytolacca genus

Rare earth elements (REEs) are now considered emerging pollutants in the environment. Phytolacca americana, an REE hyperaccumulating plant, has been proposed for the remediation of REE-contaminated soils. However, there is no REE-related information for other Phytolacca species. Here, we examined five species (P. americana, P. acinosa, P. clavigera, P. bogotensis, and P. icosandra) for their response to REEs. REE accumulation and fractionation traits both occurred on the same order of magnitude among the five species. Heavy REEs were preferentially transferred to leaves relative to light REEs. Regardless of the species, lateral root length and chlorophyll content decreased under REE exposure, and lateral roots and foliar anthocyanins increased. However, plants did not experience or only slightly experienced oxidative stress. Finally, REE exposure strongly modulated the ionome of roots and, to a lesser extent, that of leaves, with a negative correlation between REE and Mn contents. In conclusion, our study provides new data on the response of several Phytolacca species to REEs. Moreover, we highlighted that the REE accumulation trait was conserved among Phytolacca species. Thus, we provide valuable information for the phytoremediation of REE-contaminated sites since the most appropriate Phytolacca species could be selected depending on the climatic/pedological area to be remediated.