Department for Sustainable Food Process, Università Cattolica del Sacro Cuore, Piacenza, Italy.
Department for Sustainable Food Process, Università Cattolica del Sacro Cuore, Piacenza, Italy.
Sci Total Environ. 2024 Oct 1;945:174001. doi: 10.1016/j.scitotenv.2024.174001. Epub 2024 Jun 13.
Micro- and nano-plastics (MNPs) in the soil can impact the microbial diversity within rhizospheres and induce modifications in plants' morphological, physiological, and biochemical parameters. However, a significant knowledge gap still needs to be addressed regarding the specific effects of varying particle sizes and concentrations on the comprehensive interplay among soil dynamics, root exudation, and the overall plant system. In this sense, different omics techniques were employed to clarify the mechanisms of the action exerted by four different particle sizes of polyethylene plastics considering four different concentrations on the soil-roots exudates-plant system was studied using lettuce (Lactuca sativa L. var. capitata) as a model plant. The impact of MNPs was investigated using a multi-omics integrated approach, focusing on the tripartite interaction between the root metabolic process, exudation pattern, and rhizosphere microbial modulation. Our results showed that particle size and their concentrations significantly modulated the soil-roots exudates-plant system. Untargeted metabolomics highlighted that fatty acids, amino acids, and hormone biosynthesis pathways were significantly affected by MNPs. Additionally, they were associated with the reduction of rhizosphere bacterial α-diversity, following a size-dependent trend for specific taxa. The omics data integration highlighted a correlation between Pseudomonadata and Actinomycetota phyla and Bacillaceae family (Peribacillus simplex) and the exudation of flavonoids, phenolic acids, and lignans in lettuce exposed to increasing sizes of MNPs. This study provides a novel insight into the potential effects of different particle sizes and concentrations of MNPs on the soil-plant continuum, providing evidence about size- and concentration-dependent effects, suggesting the need for further investigation focused on medium- to long-term exposure.
土壤中的微塑料和纳米塑料（MNPs）会影响根际中的微生物多样性，并诱导植物形态、生理和生化参数的变化。然而，关于不同粒径和浓度对土壤动态、根系分泌物和整个植物系统之间综合相互作用的具体影响，仍存在显著的知识空白。在这方面，采用不同的组学技术来阐明四种不同粒径的聚乙烯塑料在不同浓度下对土壤-根系分泌物-植物系统的作用机制，使用生菜（Lactuca sativa L. var. capitata）作为模式植物进行研究。采用多组学综合方法研究 MNPs 的影响，重点研究根系代谢过程、分泌物模式和根际微生物调节之间的三方相互作用。研究结果表明，粒径及其浓度显著调节土壤-根系分泌物-植物系统。非靶向代谢组学表明，脂肪酸、氨基酸和激素生物合成途径受到 MNPs 的显著影响。此外，它们与根际细菌α多样性的减少有关，呈现出随粒径大小变化的趋势。组学数据集成突出了假单胞菌属和放线菌门与芽孢杆菌科（短芽孢杆菌）之间的相关性，以及在生菜暴露于不同粒径的 MNPs 时，类黄酮、酚酸和木质素的分泌之间的相关性。本研究提供了关于不同粒径和浓度的 MNPs 对土壤-植物连续体的潜在影响的新见解，为关于粒径和浓度依赖性效应的证据提供了证据，表明需要进一步关注中-长期暴露的研究。
