Department of Environmental Toxicology, The Institute for Environmental and Human Health, Texas Tech University, P.O. Box 41163, Lubbock, Texas, 79409, USA.
United State Department of Agriculture- Agriculture Research Service-Cropping Systems Research Laboratory, 3810 4th St, Lubbock, TX, 79415, USA.
Chemosphere. 2020 Oct;256:127042. doi: 10.1016/j.chemosphere.2020.127042. Epub 2020 May 11.
Carbon nanotube (CNT) applications are increasing in consumer products, including agriculture devices, making them an important contaminant to study in the field of plant nanotoxicology. Several studies have observed the uptake and effects of CNTs in plants. However, in other studies differing results were observed on growth and physiology depending on the plant species and type of CNT. This study focused on the effects of CNTs on plant phenotype with growth, time to flowering, fruiting time as endpoints, and physiology, through amino acid and phytohormone content, in tomato after exposure to multiple types of CNTs. Plants grown in CNT-contaminated soil exhibited a delay in early growth and flowering (especially in treatments of 1 mg/kg multi-walled nanotubes (MWNTs), 10 mg/kg MWNTs, and 1 mg/kg MWNTs-COOH). However, CNTs did not affect plant growth or height later in the life cycle. No significant differences in abscisic acid (ABA) and citrulline content were observed between the treated and control plants. However, single-walled nanotube (SWNT) exposure significantly increased salicylic acid (SA) content in tomato. These results suggest that SWNTs may elicit a stress response in tomatoes. Results from this study offer more insight into how plants respond and acclimate to CNTs. These results will lead to a better understanding of CNT impact on plant phenotype and physiology.
碳纳米管（CNT）在消费品中的应用日益增多，包括农业设备，因此它们成为植物纳米毒理学领域中重要的研究污染物。已有多项研究观察到 CNT 在植物中的摄取和作用。然而，在其他研究中，由于植物种类和 CNT 类型的不同，观察到了生长和生理方面的不同结果。本研究重点研究了 CNT 对植物表型的影响，以生长、开花时间、结果时间为终点，并通过暴露于多种 CNT 后番茄中的氨基酸和植物激素含量来研究其生理特性。在 CNT 污染土壤中生长的植物表现出早期生长和开花的延迟（尤其是在 1mg/kg 多壁 CNT（MWNTs）、10mg/kg MWNTs 和 1mg/kg MWNTs-COOH 处理中）。然而，CNTs 在后一生命周期中并不影响植物的生长或高度。在处理和对照植物之间，脱落酸（ABA）和瓜氨酸含量没有观察到显著差异。然而，单壁 CNT（SWNT）暴露显著增加了番茄中的水杨酸（SA）含量。这些结果表明，SWNTs 可能会在番茄中引发应激反应。本研究的结果提供了更多关于植物如何对 CNT 做出反应和适应的信息。这些结果将有助于更好地理解 CNT 对植物表型和生理的影响。
