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Zinc application facilitates the turnover of organic phosphorus in rice rhizosphere soil by modifying microbial communities

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Abstract

Aims

Zn is always co-fertilized with N and P fertilizers to increase crop yield production in agriculture. Although strong interactions between Zn and P have been recognized, how Zn affects soil P transformation mediated by microorganisms is not completely clear.

Methods

We planted rice plants in soils with different combinations of P and Zn supply, and analyzed the P transformation, bacterial and fungal communities, enzyme activities and gene expressions in rhizosphere soil.

Results

Zn application promoted rice growth and P uptake, increased available P, but decreased the proportion of organic P in rhizosphere soil after Zn supply under moderate P condition. Although Zn application did not affect either bacterial or fungal diversity, it clearly elevated PSB abundances including Saccharimonadales, Sphingomonas, Flavisolibacter, Gemmatirosa, subgroup_6, and subgroup_7, but significantly decreased the abundances of pathogenic fungi Curvularia and Fusarium under moderate P condition. Furthermore, the acid phosphatase activity increased 12.70%, the phoC, phoD, ppk, and pqqc expression levels increased to 1.88-fold, 4.99-fold, 2.86-fold, and 5.07-fold, respectively, after Zn supply under moderate P condition.

Conclusion

Zn application could facilitate the turnover of organic P into inorganic form and improve P availability by increasing PSB abundances, acid phosphatase activity, and functional gene expression levels. This positive effect of Zn on soil P transformation strongly depended on the environmental P conditions, as no obvious changes were displayed under high P condition. Therefore, Zn co-fertilized with appropriate P is an effective strategy to enhance P availability in rice rhizosphere soil to improve plant growth and P uptake.

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Abbreviations

Zn:

Zinc

P:

Phosphorus

N:

Nitrogen

Pi:

Inorganic phosphorus

Po:

Organic phosphorus

W-P:

Water soluble P

Al-P:

Aluminum bound P

Fe-P:

Iron bound P

Ca-P:

Calcium bound P

O-P:

Occluded P

SOP:

Soil organic P

A-N:

Alkali-hydrolyzed nitrogen

A-K:

Available potassium

OM:

Organic matter

IE-Zn:

Acid extraction zinc

R-Zn:

Reducible zinc

O-Zn:

Oxidizable zinc

SR-Zn:

Solid residue zinc

PSB:

Phosphorus solubilizing bacteria

PSM:

Phosphorus solubilizing microorganism

PcoA:

Principal coordinate analysis

RDA:

Redundancy analysis

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Acknowledgements

This work was supported by grants from the National Key R&D Program of China (2021YFD1901203) and Fundamental Research Funds for the Central Universities of China (2662019FW011).

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Haihan Lv and Hongmei Cai contributed to the study conception and design. Material preparation, data collection and analysis were performed by Haihan Lv and Jingli Ding. The first draft of the manuscript was written by Jingli Ding and Hongmei Cai, and Lin Zhang and Chuang Wang commented on previous versions of the manuscript. All authors read and approved the final manuscript.

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Correspondence to Hongmei Cai.

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Lv, H., Ding, J., Zhang, L. et al. Zinc application facilitates the turnover of organic phosphorus in rice rhizosphere soil by modifying microbial communities. Plant Soil 498, 77–92 (2024). https://doi.org/10.1007/s11104-022-05810-w

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