Uptake, transport, distribution and Bio-effects of SiO2 nanoparticles in Bt-transgenic cotton

Abstract

BackgroundSiO2 nanoparticle is one of the most popular nanomaterial which has been used in various fields, such as wastewater treatment, environmental remediation, food processing, industrial and household applications, biomedicine, disease labeling, and biosensor, etc. In agriculture, the use of SiO2 nanoparticles as insecticide, carriers in drug delivery, or in uptake and translocation of nutrient elements, etc., has been given attention. However, the effects of nanoparticles on plants have been seldom studied. In this work, the toxicity of SiO2 nanoparticles and their uptake, transport, distribution and bio-effects have been investigated in Bt-transgenic cotton.MethodsThe phytotoxic effects of SiO2 nanoparticles were exhibited in Bt-transgenic cotton with different SiO2 concentrations of 0, 10, 100, 500 and 2000 mg.L−1 for 3 weeks through dry biomasses, nutrient elements, xylem sap, enzymes activities, and hormone concentrations. The uptake and distribution of nanoparticles by the plants were confirmed using transmission electron microscopy (TEM).ResultsThe SiO2 nanoparticles decreased significantly the plant height, shoot and root biomasses; the SiO2 nanoparticles also affected the contents of Cu, Mg in shoots and Na in roots of transgenic cotton; and SOD activity and IAA concentration were significantly influenced by SiO2 nanoparticles. In addition, SiO2 nanoparticles were present in the xylem sap and roots as examined by TEM showing that the SiO2 nanoparticles were transported from roots to shoots via xylem sap.ConclusionsThis is the first report of the transportation of SiO2 nanoparticles via xylem sap within Bt-transgenic cotton. This study provides direct evidence for the bioaccumulation of SiO2 nanoparticles in plants, which shows the potential risks of SiO2 nanoparticles impact on food crops and human health.

Magnetite (Fe3O4) Nanoparticles Alleviate Growth Inhibition and Oxidative Stress Caused by Heavy Metals in Young Seedlings of Cucumber (Cucumis Sativus L)

“…Some plants considered as stable to heavy metals can transport higher concentration of heavy metals from root to leaf [18]. The results were supported by the report of Yilmaz et al [31] for Pb accumulation in roots and those of Jadia and Fulekar [10] and Wang et al [28] for Zn accumulation in shoots. In this study, accumulation heavy metals were significantly reduced in cucumber seedlings with the addition of nano-Fe3O4 ( Table 2).…”

Magnetic (Fe3O4) Nanoparticles Reduce Heavy Metals Uptake and Mitigate Their Toxicity in Wheat Seedling

“…The agglomeration of nano-Fe 3 O 4 in water was evaluated using Dynamic Light Scattering (DLS) equipment (ZETA SIZER 90, Nano series, Malvern, UK). analyses of superoxide dismutase (SOD), peroxidase (POD) activities and malondialdehyde (MDA) contents as previously described by [34].…”

“…The fresh roots or shoots (0.2 g) from each treatment were homogenized with 1.8 mL of 0.05 M sodium phosphate buffer (pH 7.8) under ice bath to make 10% sample compound liquid. The homogenate was centrifuged at 10000× g and 4 • C for 15 min, and the supernatant collected for the analyses of superoxide dismutase (SOD), peroxidase (POD) activities and malondialdehyde (MDA) contents as previously described by [34].…”

Response of Jatropha integerrima Plants Irrigated with Different Levels of Saline Water to Nano Silicon and Gypsum

“…While the proper effect of foliar application of nano silicon particles on vegetative and flowering parameters may be due to its effect on promoting absorption of water and fertilizers, enhancing transport of some elements in xylem sap, increasing enzymes such as nitrate reductase, increasing concentration of IAA hormone and antioxidant activity (Lu et al, 2002;Le et al, 2014).…”