Polyvinyl chloride and polybutylene adipate microplastics affect peanut and rhizobium symbiosis by interfering with multiple metabolic pathways

• Published in: Journal of hazardous materials 2024-08, Vol.475, p.134897, Article 134897
• Main Authors: Wu, Juxiang, Wu, Zhengfeng, Yu, Tianyi, Zhang, Jiancheng, Zhang, Zhimeng, Wang, Hongfeng, Zheng, Yongmei, Yang, Jishun, Wu, Yue
• Format: Article
• Language: English
• Subjects: Arachis - drug effects; Arachis - metabolism; Arachis - microbiology; Bradyrhizobium - drug effects; Bradyrhizobium - metabolism; Metabolic Networks and Pathways - drug effects; Microplastics - toxicity; MPs stresses; Nodulation; PBAT-MPs; Polyesters - metabolism; Polyvinyl Chloride; PVC-MPs; Rhizobium - drug effects; Rhizobium - metabolism; Soil Pollutants - metabolism; Soil Pollutants - toxicity; Symbiosis; Transcriptome
• ISSN: 0304-3894; 1873-3336; 1873-3336
• DOI: 10.1016/j.jhazmat.2024.134897

Microplastics (MPs), widely presented in cultivated soil, have caused serious stresses on crop growth. However, the mechanism by which MPs affect legumes and rhizobia symbiosis is still unclear. Here, peanut seedlings were inoculated with Bradyrhizobium zhanjiangense CCBAU 51778 and were grown in vermiculite with 3 %/5 % (w/w) addition of PVC (polyvinyl chloride)-MPs/PBAT (polybutylene adipate)-MPs. PVC-MPs and PBAT-MPs separately decreased nodule number by 33–100 % and 2.62–80.91 %. Transcriptome analysis showed that PVC-MPs affected more DEGs (differentially expressed genes) than PBAT-MPs, indicating PVC-MPs were more devastating for the symbiosis than PBAT-MPs. Functional annotation revealed that PVC-MPs and PBAT-MPs enriched DEGs related to biosynthesis pathways such as flavonoid, isoflavonoid, and phenylpropanoid, in peanut. And when the dose increased from 3 % to 5 %, PVC-MPs mainly enriched the pathways of starch and sucrose metabolism, alanine, aspartate and glutamate metabolism, diterpenoid biosynthesis, etc.; PBAT-MPs enriched cysteine and methionine metabolism, photosynthesis, MAPK signaling, and other pathways. These significantly enriched pathways functioned in reducing nodule number and promoting peanut tolerance to MPs stresses. This study reveals the effect of PVC-MPs and PBAT-MPs on peanut and rhizobium symbiosis, and provides new perspectives for legume production and environmental safety. [Display omitted] •Polyvinyl chloride (PVC)-MPs and polybutylene adipate (PBAT)-MPs significantly reduce peanut nodule number.•PVC-MPs is more devastating than PBAT-MPs for the symbiosis between peanut and rhizobium.•Peanut differential transcriptional response is existed according to the type and concentration of MPs.