Microplastic exposure inhibits nitrate uptake and assimilation in wheat plants.
Environ Pollut
; 360: 124626, 2024 Nov 01.
Article
em En
| MEDLINE
| ID: mdl-39084589
ABSTRACT
Microplastic (MP) contamination in soil severely impairs plant growth. However, mechanisms underlying the effects of MPs on plant nutrient uptake remain largely unknown. In this study, we revealed that NO3- content was significantly decreased in shoots and roots of wheat plants exposed to high concentrations (50-100 mg L-1) of MPs (1 µm and 0.1 µm; type polystyrene) in the hydroponic solution. Isotope labeling experiments demonstrated that MP exposure led to a significant inhibition of NO3- uptake in wheat roots. Further analysis indicated that the presence of MPs markedly inhibited root growth and caused oxidative damage to the roots. Additionally, superoxide dismutase and peroxidase activities in wheat roots decreased under all MP treatments, whereas catalase and ascorbate peroxidase activities significantly increased under the 100 mg L-1 MP treatment. The transcription levels of most nitrate transporters (NRTs) in roots were significantly downregulated by MP exposure. Furthermore, exposure to MPs distinctly suppressed the activity of nitrate reductase (NR) and nitrite reductase (NiR), as well as the expression levels of their coding genes in wheat shoots. These findings indicate that a decline in root uptake area and root vitality, as well as in the expression of NRTs, NR, and NiR genes caused by MP exposure may have adverse effects on NO3- uptake and assimilation, consequently impairing normal growth of plants.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Poluentes do Solo
/
Triticum
/
Raízes de Plantas
/
Microplásticos
/
Nitratos
Idioma:
En
Revista:
Environ Pollut
/
Environ. pollut
/
Environmental pollution
Assunto da revista:
SAUDE AMBIENTAL
Ano de publicação:
2024
Tipo de documento:
Article
País de publicação:
Reino Unido