School of Life Sciences and Medicine, Shandong University of Technology, No. 266 Xincun West Road, Zibo, 255000, Shandong, China; Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, China.
School of Geography, Earth and Environmental Science, University of Birmingham, B15 2TT, Birmingham, UK.
Environ Pollut. 2022 May 1;300:118938. doi: 10.1016/j.envpol.2022.118938. Epub 2022 Feb 1.
The impact of CeO nanoparticles (NPs) on plant physiology and soil microcosm and the underlying mechanism remains unclear to date. This study investigates the effect of CeO NPs on plant growth and soil microbial communities in both the rhizosphere of cucumber seedlings and the surrounding bulk soil, with CeCl as a comparison to identify the contribution of the particulate and ionic form to the phytotoxicity of CeO NPs. The results show that Ce was significantly accumulated in the cucumber tissue after CeO NPs exposure. In the roots, 5.3% of the accumulated Ce has transformed to Ce. This transformation might take place prior to uptake by the roots since 2.5% of CeO NPs was found transformed in the rhizosphere soil. However, the transformation of CeO NPs in the bulk soil was negligible, indicating the critical role of rhizosphere chemistry in the transformation. CeO NPs treatment induced oxidative stress in the roots, but the biomass of the roots was significantly increased, although the Vitamin C (Vc) content and soluble sugar content were decreased and mineral nutrient contents were altered. The soil enzymatic activity and the microbial community in both rhizosphere and bulk soil samples were altered, with rhizosphere soil showing more prominent changes. CeCl treatment induced similar effects although less than CeO NPs, suggesting that Ce released from CeO NPs contributed to the CeO NPs induced impacts on soil health and plant physiology.
目前，CeO 纳米颗粒（NPs）对植物生理学和土壤微生态的影响及其潜在机制尚不清楚。本研究调查了 CeO NPs 对黄瓜幼苗根际和周围原状土壤中植物生长和土壤微生物群落的影响，以 CeCl 作为比较，以确定颗粒和离子形式对 CeO NPs 植物毒性的贡献。结果表明，CeO NPs 暴露后，Ce 明显在黄瓜组织中积累。在根部，积累的 Ce 中有 5.3%转化为 Ce。这种转化可能发生在根系吸收之前，因为在根际土壤中发现有 2.5%的 CeO NPs 发生了转化。然而，在原状土壤中 CeO NPs 的转化可以忽略不计，这表明根际化学在转化中起着关键作用。CeO NPs 处理诱导了根的氧化应激，但根的生物量显著增加，尽管维生素 C（Vc）含量、可溶性糖含量降低，矿质养分含量发生了改变。土壤酶活性和根际及原状土壤样品中的微生物群落发生了改变，根际土壤的变化更为明显。CeCl 处理引起了类似的影响，但小于 CeO NPs，这表明 CeO NPs 释放的 Ce 对 CeO NPs 诱导的土壤健康和植物生理学的影响有贡献。
