College of Environmental Science and Engineering, Yangzhou University, Yangzhou, 225127, China.
College of Environmental Science and Engineering, Yangzhou University, Yangzhou, 225127, China.
Plant Physiol Biochem. 2022 Nov 15;191:1-9. doi: 10.1016/j.plaphy.2022.09.012. Epub 2022 Sep 21.
Croplands have become a hotspot for antibiotic and microplastic (MP) pollution. However, little is known regarding their combined effects on crops. In this study, the individual and combined effects of oxytetracycline (OTC) and three MPs (i.e., polypropylene (PP), polyamide (PA), and polyvinylchloride (PVC)) on cherry radish were investigated using pot experiments. Individually, OTC (50 mg kg), PA (2%, w/w), and PP (2%, w/w) induced negligible effects on cherry radish biomass and the root/shoot ratio. However, PVC (2%, w/w) significantly inhibited cherry radish growth; that is, its shoot and root fresh weight decreased by 46.2% and 81.1%, respectively. In the combined exposure groups, OTC alleviated the adverse effects of PVC on the cherry radish leaf number and shoot fresh weight. This was linked to that OTC increased the content of photosynthetic pigments. Superoxide dismutase activity in cherry radish roots was inhibited to different extents in all treatment groups except for the PA and PVC treatments. Malondialdehyde (MDA) content in cherry radish roots increased in all treatment groups, suggesting that both OTC and MPs caused oxidative damage to cherry radish root cells, therefore inhibiting cherry radish root growth. However, the presence of OTC non-significantly changed the effects of MPs on cherry radish roots. Irrespective of OTC presence, MPs induced a reduction in the root/shoot ratio of cherry radish, suggesting that the inhibitory effect of MPs on cherry radish roots was stronger than that on shoots. These findings contribute to the evaluation of the phytotoxicity of antibiotics and MPs in soil-vegetable systems.
农田已成为抗生素和微塑料（MP）污染的热点区域。然而，对于它们对作物的联合影响，人们知之甚少。在这项研究中，采用盆栽实验研究了土霉素（OTC）和三种 MPs（即聚丙烯（PP）、聚酰胺（PA）和聚氯乙烯（PVC））对樱桃萝卜的单独和联合影响。单独使用 OTC（50 mg kg）、PA（2%，w/w）和 PP（2%，w/w）对樱桃萝卜生物量和根/茎比几乎没有影响。然而，PVC（2%，w/w）显著抑制了樱桃萝卜的生长；即其地上部和根鲜重分别下降了 46.2%和 81.1%。在联合暴露组中，OTC 减轻了 PVC 对樱桃萝卜叶片数和地上部鲜重的不利影响。这与 OTC 增加了光合色素的含量有关。除 PA 和 PVC 处理外，所有处理组均不同程度地抑制了樱桃萝卜根中超氧化物歧化酶的活性。所有处理组中樱桃萝卜根中的丙二醛（MDA）含量均增加，表明 OTC 和 MPs 均对樱桃萝卜根细胞造成氧化损伤，从而抑制了樱桃萝卜根的生长。然而，OTC 的存在并没有显著改变 MPs 对樱桃萝卜根的影响。无论是否存在 OTC，MPs 都会降低樱桃萝卜的根/茎比，这表明 MPs 对樱桃萝卜根的抑制作用强于对地上部的抑制作用。这些发现有助于评估抗生素和 MPs 在土壤-蔬菜系统中的植物毒性。
