Influence of Cerium Oxide Nanoparticles on Two Terrestrial Wild Plant Species

Abstract

Most current studies on the relationships between plans and engineered nanomaterials (ENMs) are focused on food crops, while the effects on spontaneous plants have been neglected so far. However, from an ecological perspective, the ENMs impacts on the wild plants could have dire consequences on food webs and ecosystem services. Therefore, they should not be considered less critical. A pot trial was carried out in greenhouse conditions to evaluate the growth of Holcus lanatus L. (monocot) and Diplotaxis tenuifolia L. DC. (dicot) exposed to cerium oxide nanoparticles (nCeO2). Plants were grown for their entire cycle in a substrate amended with 200 mg kg−1nCeO2 having the size of 25 nm and 50 nm, respectively. nCeO2 were taken up by plant roots and then translocated towards leaf tissues of both species. However, the mean size of nCeO2 found in the roots of the species was different. In D. tenuifolia, there was evidence of more significant particle aggregation compared to H. lanatus. Further, biomass variables (dry weight of plant fractions and leaf area) showed that plant species responded differently to the treatments. In the experimental conditions, there were recorded stimulating effects on plant growth. However, nutritional imbalances for macro and micronutrients were observed, as well.

Phytotoxic Effect of sub‐3‐nm Crystalline Ceria Nanoparticles on the Hydroponic Growth of Daikon Radish Microgreens

“…Third, when more than one size of ceria NPs was investigated in these studies, the ceria NPs were usually observed to have higher phytotoxicity with lower concentrations. Examples include studies by Hernandez‐Viezcas et al ., [31] Zhang et al ., [39] and Lizzi et al [41] . Among all these studies which used commercial ceria NPs of sizes ≥6 nm or NPs with a fairly large size range, our current study demonstrated that smaller sub‐3‐nm ceria NPs could induce observable phytotoxicity at the lowest concentration (0.1 ppm).…”

Divergent effects of cerium oxide nanoparticles alone and in combination with cadmium on nutrient acquisition and the growth of maize (Zea mays)

“…The application of CeO 2 -NPs through difference sources and concentrations has some beneficial effects on plants ( Cao et al., 2017 ; Fox et al., 2020 ; Lizzi et al., 2021 ), but the generalized effects cannot be defined at once due to the divergence in the effects of bulk and ionic parts of cerium ( Zhang et al., 2015 ; Barrios et al., 2016 ; Lizzi et al., 2021 ). The size of CeO 2 -NPs can limit their entry into plant cells as membrane pore size can reduce the translocation of NPs via cross root epidermal cell membranes ( Ma et al., 2010a ; Ma et al., 2010b ; Rico et al., 2011 ), where these NPs tend to adopt apoplastic pathways.…”