title: Comparison of the toxicity of silver nanoparticles and silver ions on the growth of terrestrial plant model Arabidopsis thaliana.
abstract: Silver nanoparticles (AgNPs) are one of the most widely used nanomaterials, but the mechanism of AgNP toxicity in terrestrial plants is still unclear. We compared the toxic effects of AgNPs and Ag+ on Arabidopsis thaliana at the physiological, ultrastructural and molecular levels. AgNPs did not affect seed germination; however, they showed stronger inhibitory effect on root elongation than Ag+. The results of transmission electron microscopy and metal content analysis showed that AgNPs could be accumulated in leaves. These absorbed AgNPs disrupted the thylakoid membrane structure and decreased chlorophyll content, which can inhibit plant growth. By comparison, a small amount of Ag+ was absorbed by seedlings, and it did not pronouncedly affect chloroplast structure and other metal ion absorption as AgNPs did. Compared with Ag+, AgNPs could alter the transcription of antioxidant and aquaporin genes, indicating that AgNPs changed the balance between the oxidant and antioxidant systems, and also affected the homeostasis of water and other small molecules within the plant body. All the data from physiological, ultrastructural and molecular levels suggest that AgNPs were more toxic than Ag+.
authors: College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032, China.
authors: Haifeng
authors: H
authors: Qian
authors: College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032, China.
authors: Xiaofeng
authors: X
authors: Peng
authors: College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032, China.
authors: Xiao
authors: X
authors: Han
authors: College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032, China.
authors: Jie
authors: J
authors: Ren
authors: College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032, China.
authors: Liwei
authors: L
authors: Sun
authors: College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032, China.
authors: Zhengwei
authors: Z
authors: Fu
mesh_terms: D017360:Arabidopsis / Q000187:drug effects* / Q000254:growth & development; D002412:Cations; D053768:Metal Nanoparticles / Q000633:toxicity*; D046529:Microscopy, Electron, Transmission; D008954:Models, Biological; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012834:Silver / Q000737:chemistry*
chemical_list: D002412:Cations; D012834:Silver