Faculty of Science and Technology, Free University of Bozen-Bolzano, Bolzano, Italy.
Competence Centre for Plant Health, Free University of Bozen-Bolzano, Bolzano, Italy.
Sci Total Environ. 2022 Sep 20;840:156678. doi: 10.1016/j.scitotenv.2022.156678. Epub 2022 Jun 13.
Microplastics (MPs) are ubiquitous contaminants. In recent decades, the hazardous impacts of MPs on the environment have raised significant concern. However, little attention has been focused on the interaction between MPs and plants in terrestrial agroecosystems. This study aims to investigate the effects of polyethylene microspheres (PE-MS) on the germination, morphology, and metabolism of barley (Hordeum vulgare L.), cucumber (Cucumis sativus L.), and tomato (Solanum lycopersicum L.). Specifically, seeds were soaked in PE-MS solutions at three concentrations (10, 100, and 1000 mg L), while control seeds were treated with distilled water. After five days, the morphological parameters of barley (i.e., shoot and root biomass, length, and average diameter) were significantly affected by PE-MS treatment, even at the lowest concentration, without a dose dependency. On the other hand, the effect of PE-MS on the morphological parameters of cucumber and tomato was evident only at the highest concentration (1000 mg L). PE-MS also induced metabolomic reprogramming of shoots and roots in all three plant species. There was a downregulation of fatty acids and secondary metabolites (except in tomato shoots). In addition, the response of amino acids and hormones was highly heterogeneous among species and plant parts. In particular, the response of metabolites changed within species among different plant parts. In conclusion, we found a strong influence of MS-PE on the metabolic profile of the three plant species and a positive priming of seedling growth, especially in barley, where all the morphological parameters considered were significantly improved. Further investigations are needed to fully understand the mechanisms underlying MP-plant interactions, especially in the long term.
微塑料（MPs）是普遍存在的污染物。近几十年来，MPs 对环境的危害影响引起了人们的高度关注。然而，人们对 MPs 与陆地农业生态系统中植物之间的相互作用关注甚少。本研究旨在探讨聚乙烯微球（PE-MS）对大麦（Hordeum vulgare L.）、黄瓜（Cucumis sativus L.）和番茄（Solanum lycopersicum L.）萌发、形态和代谢的影响。具体来说，种子在三种浓度（10、100 和 1000 mg L）的 PE-MS 溶液中浸泡，而对照种子用蒸馏水处理。五天后，PE-MS 处理显著影响大麦的形态参数（即芽和根生物量、长度和平均直径），即使在最低浓度下，也没有剂量依赖性。另一方面，PE-MS 对黄瓜和番茄形态参数的影响仅在最高浓度（1000 mg L）时明显。PE-MS 还诱导了三种植物 shoot 和根中的代谢组重编程。脂肪酸和次生代谢物（番茄 shoot 除外）下调。此外，氨基酸和激素的响应在物种和植物部位之间高度异质。特别是，在不同植物部位之间，代谢物的响应在种内发生变化。总之，我们发现 MS-PE 对三种植物物种的代谢谱有很强的影响，并对幼苗生长有积极的促进作用，尤其是在大麦中，所有考虑的形态参数都有显著提高。需要进一步研究以充分了解 MPs-植物相互作用的机制，尤其是在长期方面。
