Full-Length 16S rRNA Sequencing Reveals That Silicon Fertilization Enhances Sugarcane Yield and Heavy Metal Tolerance by Reshaping the Rhizosphere Microbiome
Year: 2026
Type: article
Abstract: Silicon (Si) depletion in intensively managed tropical soils may limit the performance of silicophilic crops such as sugarcane. This field study investigated granular and powdered Si-enriched compound fertilizers applied at a product rate of low (1000 kg·hm−2) and high (1250 kg·hm−2) doses, evaluating impacts on: (1) sugarcane agronomic traits and edaphic properties; (2) heavy metal accumulation in plant tissues and rhizosphere soil; and (3) rhizosphere bacterial communities via PacBio sequencing of full-length 16S rRNA genes. Our findings indicated that high-dose Si application (HP) significantly boosted sugarcane growth in the second cropping season (2022) compared with the control (CK), with stalk height increasing by 12.43%, stalk diameter by 8.93%, sucrose content by 21.41%, available stalk number by 21.33%, single stalk weight by 35.21%, and theoretical yield by 64.16%. High-dose powdered Si increased available nitrogen (33.89%), phosphorus (29.05%), potassium (43.42%), and soil Si (42.18%). Si amendments reduced toxic metals (Cd, Pb, Cr) by 56–75% in tissues and enriched putatively beneficial bacterial taxa (e.g., Aquabacterium, Candidatus Koribacter). Microbial community analysis revealed dose-dependent shifts in bacterial diversity, with the enrichment of putatively beneficial taxa, such as Candidatus Solibacter and Kitasatospora, in the high-dose treatment groups. A ternary plot analysis further revealed treatment-enriched genera distinct from the control. Moreover, redundancy analysis identified available potassium, soil pH, and Si as the key edaphic factors shaping rhizosphere bacterial community composition. This study offers a theoretical foundation for its application to sustainable farming towards food security. Further studies are required to explore the individual roles of these bacterial strains in the silicon-mediated plant growth.
Source: Agronomy
Language: English
Subfield: Plant Science
Domain: Life Sciences
Open Access status: gold
Estimated APC paid: $3,137
OpenAlex ID: W7225786045