Abstract：
Polyethylene microplastics (PE MPs) are the main MPs in agricultural soils and undergo oxidation upon environmental exposure. However, the influence of MP oxidation on phytotoxicity (especially for crop fruit) is still limited. This study aimed to explore the effect of PE MP oxidation on crop toxicity. Herein, a combination of plant phenotyping, metabolomic, and transcriptomic approaches was used to evaluate the effects of low-oxidation PE (LOPE) and high-oxidation PE (HOPE) on wheat growth, grain quality, and related molecular mechanisms using pot experiments. The results showed that HOPE induced a stronger inhibition of wheat growth and reduction in protein content and mineral elements than LOPE. This was accompanied by root ultrastructural damage and downregulation of carbohydrate metabolism, translation, nutrient reservoir activity, and metal ion binding gene expression. Compared with HOPE, LOPE activated a stronger plant defense response by reducing the starch content by 22.87 %, increasing soluble sugar content by 44.93 %, and upregulating antioxidant enzyme genes and crucial metabolic pathways (e.g., starch and sucrose, linoleic acid, and phenylalanine metabolism). The presence of PE MPs in the environment exacerbates crop growth inhibition and fruit quality deterioration, highlighting the need to consider the environmental and food safety implications of MPs in agricultural soils.
摘要：
聚乙烯微塑料（PEMPs）是农业土壤中的主要MPs，在暴露于环境时会发生氧化。然而,MP氧化对植物毒性（尤其是对作物果实）的影响仍然有限。本研究旨在探讨PEMP氧化对作物毒性的影响。在这里，植物表型的组合，代谢组学，和转录组学方法用于评估低氧化PE（LOPE）和高氧化PE（HOPE）对小麦生长的影响，粮食质量,以及使用盆栽实验的相关分子机制。结果表明，与LOPE相比，HOPE对小麦生长的抑制作用更强，蛋白质含量和矿质元素含量降低。这伴随着根的超微结构损伤和碳水化合物代谢的下调，翻译,养分储库活动，和金属离子结合基因表达。与希望相比,LOPE通过将淀粉含量降低22.87%，激活了更强的植物防御反应，可溶性糖含量增加44.93%，并上调抗氧化酶基因和关键的代谢途径(例如，淀粉和蔗糖，亚油酸,和苯丙氨酸代谢）。环境中PEMPs的存在加剧了作物生长抑制和果实品质恶化,强调需要考虑国会议员在农业土壤中对环境和食品安全的影响。
