Evaluating phytotoxicity of HDPE and Nylon-6,6 microplastics on wild plants, Cynodon dactylon (L.) and Portulaca grandiflora: an initiative towards soil remediation
摘要
Microplastic pollution has gained significant attention due to its environmental impacts. This study presents a simulated dump yard model to examine the toxic effects of high-density polyethylene (HDPE) and nylon-6,6 microplastics on tropical wild plants: Cynodon dactylon (L.) and Portulaca grandiflora. We assessed morphological changes using confocal laser scanning microscopy, proline and phenolic contents, chlorophyll content, and biometrical features (root and shoot height, biomass output). Microplastic-treated samples demonstrated significant declines in all measurable parameters compared to controls. Confocal microscopy revealed microplastic absorption in plant leaf tissues and root structures via xylem transport. These results support a transfer mechanism from root to leaf sections via apoplast and symplast pathways, with microplastics entering plant cells through endocytosis and traversing cytoplasmic continuity via plasmodesmata. This study highlights significant knowledge gaps in microplastic-contaminated soil and provides insights for developing sustainable agroecosystem strategies to address microplastic pollution in terrestrial environments.