Visual Observation of Polystyrene Microplastics/Nanoplastics in Peanut Seedlings and Their Effects on Growth and the Antioxidant Defense System

作者：Yuyang Li, Xinyi Huang, Qiang Lv, Zhanqiang Ma, Minhua Zhang, Jing Liu, Li Fan, Xuejiao Yan, Nianyuan Jiao, Aneela Younas, Muhammad Shaaban, Jiakai Gao, Yanfang Wang, Ling Liu · 发表于：Agronomy · 年份：2025 · DOI：10.3390/agronomy15081895 · 被引用次数：4 · 研究领域：Microplastics and Plastic Pollution、Nanoparticles: synthesis and applications、biodegradable polymer synthesis and properties

Peanut cultivation is widely practiced using plastic mulch film, resulting in the accumulation of microplastics/nanoplastics (MPs/NPs) in agricultural soils, potentially negatively affecting peanut growth. To investigate the effects of two polystyrene (PS) sizes (5 μm, 50 nm) and three concentrations (0, 10, and 100 mg L−1) on peanut growth, photosynthetic efficiency, and physiological characteristics, a 15-day hydroponic experiment was conducted using peanut seedlings as the experimental material. The results indicated that PS-MPs/NPs inhibited peanut growth, reduced soil and plant analyzer development (SPAD) values (6.7%), and increased levels of malondialdehyde (MDA, 22.0%), superoxide anion (O2−, 3.8%) superoxide dismutase (SOD, 16.1%) and catalase (CAT, 12.1%) activity, and ascorbic acid (ASA, 12.6%) and glutathione (GSH, 9.1%) contents compared to the control. Moreover, high concentrations (100 mg L−1) of PS-MPs/NPs reduced the peanut shoot fresh weight (16.1%) and SPAD value (7.2%) and increased levels of MDA (17.1%), O2− (5.6%), SOD (10.6%), POD (27.2%), CAT (7.3%), ASA (12.3%), and GSH (6.8%) compared to low concentrations (10 mg L−1) of PS-MPs/NPs. Notably, under the same concentration, the impact of 50 nm PS-NPs was stronger than that of 5 μm PS-MPs. The peanut shoot fresh weight of PS-NPs was lower than that of PS-MPs by an average of 7.9%. Additionally, we found that with an increasing exposure time of PS-MPs/NPs, the inhibitory effect of low concentrations of PS...