Instituto Federal Goiano, Campus Rio Verde, Rio Verde, GO, 75.901-970, Brazil.
Instituto Federal Goiano, Campus Rio Verde, Rio Verde, GO, 75.901-970, Brazil.
Environ Pollut. 2021 Mar 1;272:115971. doi: 10.1016/j.envpol.2020.115971. Epub 2020 Nov 6.
Atrazine is an herbicide commonly used in several countries. Due to its long half-life, associated with its use in large scales, atrazine residues remain as environmental pollutants in water bodies. Phytoremediation is often pointed out as an interesting approach to remove atrazine from the aquatic environment, but its practical application is limited by the high toxicity of this herbicide. Here, we characterize the damages triggered by atrazine in Pistia stratiotes, evaluating the role of nitric oxide (NO), a cell-signaling molecule, in increasing the tolerance to the pollutant and the phytoremediation potential of this species. Pistia stratiotes plants were exposed to four treatments: Control; Sodium nitroprusside (SNP) (0.05 mg L); Atrazine (ATZ) (150 μg L) and ATZ + SNP. The plants remained under those conditions for 24 h for biochemical and physiological analysis and 3 days for the evaluation of relative growth rate. The presence of atrazine in plant cells triggered a series of biochemical and physiological damages, such as the increase in the generation of reactive oxygen species, damages to cell membranes, photosynthesis impairment, and negative carbon balance. Despite this, the plants maintained greater growth rates than other aquatic macrophytes exposed to atrazine and showed high bioconcentration and translocation factors. The addition of SNP, a NO donor, decreased the herbicide toxicity, with an increase of over 60% in the IC value (Inhibitor Concentration). Indeed, the NO signaling action was able to increase the tolerance of plants to atrazine, which resulted in increments in pollutant uptake and translocation, with the maintenance of overall cell (e.g. membranes) and organs (root system) structure, and the functioning of central physiological processes (e.g. photosynthesis). These factors allowed for more quickly and efficient removal of the pollutant from the environment, reducing costs, and increasing the viability of the phytoremediation process.
莠去津是一种在多个国家广泛使用的除草剂。由于其半衰期长，与大规模使用有关，莠去津残留仍然是水体中的环境污染物。植物修复通常被认为是一种从水生环境中去除莠去津的有趣方法，但由于该除草剂的高毒性，其实际应用受到限制。在这里，我们描述了莠去津对凤眼莲造成的损害，评估了一氧化氮（NO）作为一种细胞信号分子在增加对污染物的耐受性和该物种的植物修复潜力方面的作用。将凤眼莲植物暴露于四种处理中：对照；硝普钠（SNP）（0.05mg/L）；莠去津（ATZ）（150μg/L）和 ATZ+SNP。这些植物在这些条件下停留 24 小时进行生化和生理分析，停留 3 天进行相对生长率评估。莠去津在植物细胞中的存在引发了一系列生化和生理损伤，如活性氧的产生增加、细胞膜损伤、光合作用受损和负碳平衡。尽管如此，与其他暴露于莠去津的水生植物相比，这些植物保持了更高的生长速度，并表现出高的生物浓缩和迁移因子。添加 SNP，一种 NO 供体，降低了除草剂的毒性，IC 值（抑制剂浓度）增加了 60%以上。事实上，NO 信号作用能够提高植物对莠去津的耐受性，从而增加污染物的吸收和迁移，同时保持细胞（如细胞膜）和器官（根系）的整体结构以及中央生理过程（如光合作用）的正常运转。这些因素使得污染物能够更快、更有效地从环境中去除，降低成本，并提高植物修复过程的可行性。
