Abstract
This study investigated the effects of third generation exposure to cerium oxide nanoparticles (CeO(2)-NPs) on biomass, elemental and (15)N uptake, and fatty acid contents of wheat (Triticum aestivum). At low or high nitrogen treatment (48 or 112 mg N), seeds exposed for two generations to 0 or 500 mg CeO(2)-NPs per kg soil treatment were cultivated for third year in soil amended with 0 or 500 mg CeO(2)-NPs per kg soil. The results showed that parental and current exposures to CeO(2)-NPs increased the root biomass in daughter plants with greater magnitude of increase at low N than high N. When wheat received CeO(2)-NPs in year 3, root elemental contents increased primarily at low N, suggesting an important role of soil N availability in altering root nutrient acquisition. The δ(15)N ratios, previously shown to be altered by CeO(2)-NPs, were only affected by current and not parental exposure, indicating effects on N uptake and/or metabolism are not transferred from one generation to the next. Seed fatty acid composition was also influenced both by prior and current exposure to CeO(2)-NPs. The results suggest that risk assessments of NP exposure may need to include longer-term, transgenerational effects on growth and grain quality of agronomic crops.