Chen Zhangling, Carter Laura J, Banwart Steven A, Kay Paul
School of Earth and Environment, University of Leeds, Leeds, United Kingdom.
School of Geography, University of Leeds, Leeds, United Kingdom.
Front Plant Sci. 2025 Aug 28;16:1670247. doi: 10.3389/fpls.2025.1670247. eCollection 2025.
Microplastics (MPs) are emerging contaminants in agricultural soils. However, the responses of different plant species to MP stress under soil conditions across varying concentration levels, as well as the underlying mechanisms, remain insufficiently understood.
This study examined the morphological, physiological, and biochemical responses of Chinese cabbage () and cherry radish () grown in soil containing polystyrene microplastics (PS-MPs) at concentrations of 10, 50, and 100 mg/kg.
PS-MPs altered soil properties by increasing pH and water-holding capacity (WHC), which promoted early germination in both species. However, during later growth stages, MPs inhibited development in a species-specific manner. In cherry radish, root length and fruit diameter decreased by 35.0% and 20.4%, respectively, primarily due to physical blockage. In Chinese cabbage, leaf area and petiole number declined by 35.9% and 41.7%, mainly driven by soil structural disruption and nutrient loss. Notably, the most pronounced effects occurred at low (10 mg/kg) to medium (50 mg/kg) concentrations, indicating a non-linear dose-response relationship. Hierarchical regression analysis (HRA) further revealed distinct toxicity mechanisms: physical accumulation and localized hypoxia were predominant in cherry radish, whereas oxidative stress and redox imbalance played a central role in Chinese cabbage.
These findings support current ecotoxicological models and highlight the importance of plant-particle interactions in shaping crop responses. The results provide new insight into MP phytotoxicity and inform future risk assessments under realistic soil conditions.
微塑料是农业土壤中新兴的污染物。然而，不同植物物种在不同浓度水平的土壤条件下对微塑料胁迫的响应及其潜在机制仍未得到充分了解。
本研究考察了在含有浓度为10、50和100毫克/千克的聚苯乙烯微塑料（PS-MPs）的土壤中生长的大白菜（）和樱桃萝卜（）的形态、生理和生化响应。
PS-MPs通过提高土壤pH值和持水能力（WHC）改变了土壤性质，这促进了两种植物的早期萌发。然而，在后期生长阶段，微塑料以物种特异性的方式抑制了植物发育。在樱桃萝卜中，根长和果实直径分别下降了35.0%和20.4%，主要是由于物理阻塞。在大白菜中，叶面积和叶柄数量分别下降了35.9%和41.7%，主要是由土壤结构破坏和养分流失导致的。值得注意的是，最显著的影响发生在低（10毫克/千克）到中（50毫克/千克）浓度时，表明存在非线性剂量反应关系。层次回归分析（HRA）进一步揭示了不同的毒性机制：物理积累和局部缺氧在樱桃萝卜中占主导地位，而氧化应激和氧化还原失衡在大白菜中起核心作用。
这些发现支持了当前的生态毒理学模型，并突出了植物与颗粒相互作用在塑造作物响应中的重要性。研究结果为微塑料对植物的毒性提供了新的见解，并为现实土壤条件下的未来风险评估提供了参考。
