Environmental Science and Engineering PhD. Program, The University of Texas at El Paso, 500 West University Ave., El Paso, TX 79968, United States; Department of Chemistry, The University of Texas at El Paso, 500 West University Ave., El Paso, TX 79968, United States; University of California Center for Environmental Implications of Nanotechnology (UC CEIN), The University of Texas at El Paso, 500 West University Ave., El Paso, TX 79968, United States.
Environmental Science Program, Department of Geological Sciences, The University of Texas at El Paso, 500 West University Ave., El Paso, TX 79968, United States.
Sci Total Environ. 2020 May 20;718:137318. doi: 10.1016/j.scitotenv.2020.137318. Epub 2020 Feb 14.
As interest in the use of copper-based nanomaterials in agriculture continue to increase, research into their exposure effects must expand from short-term, high exposure studies to long-term studies at realistic concentrations. Long-term studies can better elucidate the implications of copper nanomaterial exposure by allowing plants to mature and adapt to higher copper concentrations. In this study, sugarcane plants were grown to maturity in large nursery pots using soils amended with one of the following treatments: Kocide 3000 (Cu(OH)), a nano-sized CuO (nCuO), a bulk-sized CuO (bCuO), copper metal nanoparticles (Cu NP), or CuCl at 20, 40, and 60 mg kg. After tissue harvesting, copper content in plant tissues, including pressed cane juice, were determined. Chlorophyll content and the activity of reactive oxygen species (ROS) related enzymes, in root tissues, were measured as an indicator of plant health. Elemental analysis revealed significant changes in root copper concentrations only upon application of the highest levels of Kocide 3000, nCuO, and Cu NP. However, translocation of copper to leaf tissues displayed consistent increases with added copper over controls. Plants treated with Kocide 3000 at 60 mg kg experienced a significant 31% decrease in cane juice yield; copper concentrations in the pressed juice of plants treated with: Kocide 3000 at 20 and 60 mg kg, nCuO at 20 and 60 mg kg, bCuO at 20 mg kg, CuCl at 40 mg kg, and Cu NP increased by at least 58%. Chlorophyll content remained comparable to controls, and there was a significant 50 to 68% decrease in superoxide dismutase (SOD) activity in plants treated with nCuO, bCuO, Cu NP, and CuCl. The results indicate that sugarcane plants exposed to the selected copper-based treatments were not adversely affected.
随着人们对铜基纳米材料在农业中应用的兴趣不断增加，对其暴露效应的研究必须从短期、高暴露研究扩展到在实际浓度下进行长期研究。长期研究可以通过允许植物成熟并适应更高的铜浓度，更好地阐明铜纳米材料暴露的影响。在这项研究中，使用以下处理方式之一在大型苗圃盆中种植成熟的甘蔗植物：Kocide 3000（Cu(OH)），纳米尺寸的 CuO（nCuO），块状尺寸的 CuO（bCuO），铜金属纳米颗粒（Cu NP）或 CuCl，浓度分别为 20、40 和 60 mg/kg。组织收获后，测定植物组织（包括压榨蔗汁）中的铜含量。根组织中活性氧（ROS）相关酶的叶绿素含量和活性被用作植物健康的指标。元素分析显示，仅在应用最高水平的 Kocide 3000、nCuO 和 Cu NP 时，根铜浓度才会发生显著变化。然而，与对照相比，铜向叶片组织的转运显示出一致的增加。用 60 mg/kg 的 Kocide 3000 处理的植物的蔗汁产量显著下降 31%；用 20 和 60 mg/kg 的 Kocide 3000、20 和 60 mg/kg 的 nCuO、20 mg/kg 的 bCuO、40 mg/kg 的 CuCl 和 Cu NP 处理的植物的压榨汁中的铜浓度增加了至少 58%。叶绿素含量与对照相比保持相当，用 nCuO、bCuO、Cu NP 和 CuCl 处理的植物中超氧化物歧化酶（SOD）活性显著下降 50%至 68%。结果表明，暴露于所选铜基处理的甘蔗植物未受到不利影响。
