Xylem- and Phloem-Based Transport of CuO Nanoparticles in Maize (Zea maysL.)

Citations Over TimeTop 1% of 2012 papers

Abstract

This work reports on the toxicity of CuO nanoparticles (NPs) to maize (Zea mays L.) and their transport and redistribution in the plant. CuO NPs (100 mg L(-1)) had no effect on germination, but inhibited the growth of maize seedlings; in comparison the dissolved Cu(2+) ions and CuO bulk particles had no obvious effect on maize growth. CuO NPs were present in xylem sap as examined by transmission electron microscopy (TEM) and energy dispersive spectroscopy (EDS), showing that CuO NPs were transported from roots to shoots via xylem. Split-root experiments and high-resolution TEM observation further showed that CuO NPs could translocate from shoots back to roots via phloem. During this translocation, CuO NPs could be reduced from Cu (II) to Cu (I). To our knowledge, this is the first report of root-shoot-root redistribution of CuO NPs within maize. The current study provides direct evidence for the bioaccumulation and biotransformation of CuO NPs (20-40 nm) in maize, which has significant implications on the potential risk of NPs and food safety.

Related Papers

• → Phytophages of Xylem and Phloem: a Comparison of Animal and Plant Sap-feeders(1983)284 cited
• → Xylem to phloem transfer of solutes in fruiting shoots of legumes, studied by a phloem bleeding technique(1975)158 cited
• → Transfer of zinc from xylem to phloem in the peduncle of wheat(1994)75 cited
• → Xylem and phloem formation in chestnut (Castanea sativa Mill.) during the 2008 growing season(2011)44 cited
• → Proteolytic activity in the stem cambial region of Pinus sylvestris L. - A contribution to the specific differentiation of secondary xylem and phloem(2013)2 cited