Common duckweed is proving surprisingly resilient to pervasive nanoplastic pollution, according to a new study. Researchers from the Wuhan Botanical Garden, Chinese Academy of Sciences have decoded the plant's intricate cellular strategies for combating nanoplastic pollution, revealing a sophisticated detoxification system and surprising recovery potential.

Micro- and nanoplastics are a growing environment challenge, contaminanting aquatic ecosystems and posing risks to ecological health and environmental sustainability.

Using the combination of physiological and biochemical analyses, single-nucleus RNA sequencing, and nanoparticle tracking techniques, Prof. LIU Wenzhi's team and collaborators found that exposure to nanoplastics reduced the growth rates and root length, and disrupted photosynthetic pigments, particularly at high nanoplastics concentrations, however, this exposure did not significantly affect overall plant biomass. Notably, this physiological alterations were largely reversible after a recovery period, demonstrating the plant's remarkable resilience. Oxidative stress markers were significantly elevated during exposure and recovery, highlighting oxidative damage as a key mechanism of nanoplastics-induced cellular stress.

Importantly, single-nucleus RNA sequencing revealed cell-type-specific adaptations, with mesophyll and sheath cells showing the most pronounced transcriptional reprogramming in metabolic and stress pathways, emphasizing the critical roles of these cell types in mitigating and adapting to nanoplastics stress. Furthermore, the research revealed duckweed's ability to rapidly take up and excrete nanoplastics, underscoring an efficient detoxification system. This process mitigates physiological damage and activates targeted molecular programs for recovery and adaptation at the single-cell level.

This comprehensive, multi-scale study deciphers the molecular strategies of duckweed at the single-cell level, offering crucial mechanistic understanding of how aquatic plants interact with and survive in nanoplastic polluted environments.

The research was published in ACS Nano entitled“Nanoplastics in Duckweed: Single-Cell Responses and Recovery”. This work was supported by the National Natural Science Foundation of China, the Special Research Assistant Project, Chinese Academy of Sciences, and the Natural Science Foundation of Hubei Province.