N-(1,3-dimethylbutyl)-N′-phenyl-p-phenylenediamine (6PPD) and N-(1,3-Dimethylbutyl)-N′-phenyl-p-phenylenediamine-quinone (6PPD-Q) are the derivatives of tire wear particles (TWPs) that can enter the agricultural environment. Their negative consequences on the agricultural environment remain unknown, particularly their toxic effects on edible plants. In this experiment, the toxicity of different concentrations of 6PPD and 6PPD-Q on pakchoi (Brassica rapa L. ssp. chinensis) was explored by hydroponics. The results revealed that seed germination was inhibited by 6PPD and 6PPD-Q to various degrees. However, we observed an increase in the fresh weight of pakchoi seedling. Environmental concentration (1 μg L⁻¹) of 6PPD and 6PPD-Q significantly increased ROS levels and caused changes in antioxidant enzyme activities. The MDA content of pakchoi was significantly elevated under 6PPD-Q treatment, indicating severe oxidative damage. These results demonstrated the phytotoxicity induced by 6PPD and 6PPD-Q, which is of great significance for assessing their potential ecological risks in the environment.

中文翻译：

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6PPD及其氧化产物6PPD-Q对小白菜的药害研究


N-(1,3-二甲基丁基)-N'-苯基-对苯二胺(6PPD)和N-(1,3-二甲基丁基)-N'-苯基-对苯二胺-醌(6PPD-Q)是衍生物可能进入农业环境的轮胎磨损颗粒 (TWP) 的数量。它们对农业环境的负面影响仍然未知，特别是它们对食用植物的毒性影响。本实验通过水培法探讨了不同浓度的6PPD和6PPD-Q对小白菜（ Brassica rapa L. ssp. chinensis ）的毒性。结果表明，6PPD和6PPD-Q对种子萌发有不同程度的抑制作用。然而，我们观察到小白菜幼苗的鲜重有所增加。 6PPD和6PPD-Q的环境浓度（1 μg L ^-1 ）显着增加ROS水平并引起抗氧化酶活性的变化。 6PPD-Q处理后小白菜的MDA含量显着升高，表明氧化损伤严重。这些结果证明了6PPD和6PPD-Q的植物毒性，对于评估其在环境中的潜在生态风险具有重要意义。