Modulation of rhizosphere microbial community and metabolites by bio-functionalized nanoscale silicon oxide alleviates cadmium-induced phytotoxicity in bayberry plants

• Published in: The Science of the total environment Vol. 933; p. 173068
• Main Authors: Ahmed, Temoor, Shou, Linfei, Guo, Junning, Noman, Muhammad, Qi, Yetong, Yao, Yanlai, Masood, Hafiza Ayesha, Rizwan, Muhammad, Ali, Md. Arshad, Ali, Hayssam M., Li, Bin, Qi, Xingjiang
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 10.07.2024
• Subjects: Antioxidants; Bacterial community; Biogenic nanoparticles; Cadmium - toxicity; Heavy metals; Metabolomics; Microbiota - drug effects; Myrica; Myrica rubra; Nanoparticles - toxicity; Rhizosphere; Silicon; Silicon Dioxide; Soil Microbiology; Soil Pollutants - toxicity; Antioxidants; Metabolomics; Biogenic nanoparticles; Myrica rubra; Silicon; Bacterial community; Heavy metals
• ISSN: 0048-9697; 1879-1026
• DOI: 10.1016/j.scitotenv.2024.173068

Cadmium (Cd) is an extremely toxic heavy metal that can originate from industrial activities and accumulate in agricultural soils. This study investigates the potential of biologically synthesized silicon oxide nanoparticles (Bio-SiNPs) in alleviating Cd toxicity in bayberry plants. Bio-SiNPs were synthesized using the bacterial strain Chryseobacterium sp. RTN3 and thoroughly characterized using advanced techniques. A pot experiment results demonstrated that Cd stress substantially reduced leaves biomass, photosynthesis efficiency, antioxidant enzyme activity, and induced oxidative damage in bayberry (Myrica rubra) plants. However, Bio-SiNPs application at 200 mg kg−1 significantly enhanced plant biomass, chlorophyll content (26.4 %), net photosynthetic rate (8.6 %), antioxidant enzyme levels, and mitigated reactive oxygen species production under Cd stress. Bio-SiNPs modulated key stress-related phytohormones by increasing salicylic acid (13.2 %) and abscisic acid (13.7 %) contents in plants. Bio-SiNPs augmented Si deposition on root surfaces, preserving normal ultrastructure in leaf cells. Additionally, 16S rRNA gene sequencing demonstrated that Bio-SiNPs treatment favorably reshaped structure and abundance of specific bacterial groups (Proteobacteria, Actinobacteriota, and Acidobacteriota) in the rhizosphere. Notably, Bio-SiNPs application significantly modulated the key metabolites (phenylacetaldehyde, glycitein, maslinic acid and methylmalonic acid) under both normal and Cd stress conditions. Overall, this study highlights that bio-nanoremediation using Bio-SiNPs enhances tolerance to Cd stress in bayberry plants by beneficially modulating biochemical, microbial, and metabolic attributes. [Display omitted] •Biofunctionalized silicon nanoparticles (Bio-SiNPs) were synthesized using bacterial strain Chryseobacterium sp. RTN3.•Bio-SiNPs amendments substantially improved the photosynthesis, antioxidant enzymes, and reduced ROS in bayberry plants.•Bio-SiNPs application modulate phytohormones and preserving cellular ultrastructure of bayberry.•Bio-SiNPs modulated beneficial rhizosphere metabolites and reshaped microbial community structure, enhancing Cd tolerance.•The present study highlights sustainable bio-nanoremediation approach to alleviate Cd stress in crops.