Elucidating the effect of biofertilizers on bacterial diversity in maize rhizosphere soil

PLoS One. 2021 Apr 23;16(4):e0249834. doi: 10.1371/journal.pone.0249834. eCollection 2021.

Abstract

This study was conducted to investigate the effect of biofertilizers on the structure and diversity of the rhizosphere bacterial community of maize. Different biofertilizers were applied to maize. The physical and chemical properties of rhizosphere soil samples were analyzed and the rhizosphere bacteria were analyzed by 16S amplicon sequencing. The results showed that treatment with Bacillus licheniformis and B. amyloliquefaciens as biofertilizers increased the soil organic matter (SOM), total nitrogen, total phosphorus (TP), available phosphorus (AP), and available potassium (AK) contents, indicating that the plant growth-promoting rhizobacteria in the biofertilizers might help the host plant to produce root exudates that, in return, recruit beneficial communities due to available sugars, amino acids, organic acids, vitamins, and polymers. The rhizosphere of maize treated with B. subtilis biofertilizer had the highest diversity and richness. However, the rhizosphere treated with the combined bacterial strains had the lowest diversity and richness, which might be due to the directional increase of the abundance of some bacteria with special functions, but the decrease of the overall bacterial community diversity in the soil. The dominant bacterial phyla were Proteobacteria (32.2%-34.6%), Acidobacteria (15.0%-21.0%), Actinobacteria (13.1%-17.2%), and Gemmatimonadetes (9.0%-10.8%), and the dominant bacterial species were Aciditerrimonas ferrireducens JCM 15389 (4.3%-5.2%), Gemmatimonas aurantiaca (3.2%-4.1%), and Pyrinomonas methylaliphatogenes (2.1%-4.8%). The significantly enriched bacterial functions were associated with amino acid metabolism, sugar metabolism, and energy metabolism pathways. The results of a redundancy analysis showed that SOM, TP, and AK were the main factors affecting the microbial community structure in the maize rhizosphere. In conclusion, the application of biofertilizers increased the diversity and richness of the bacterial community in the maize rhizosphere soil. However, combined strain treatment was failed and not an ideal strategy due to the lowest abundance and diversity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacillus subtilis / pathogenicity
  • Crop Production / methods*
  • Fertilizers / microbiology*
  • Microbiota*
  • Rhizosphere*
  • Soil Microbiology
  • Zea mays / growth & development
  • Zea mays / metabolism
  • Zea mays / microbiology*

Substances

  • Fertilizers

Grants and funding

This work was supported by the National Key Research and Development Program [grant number 2018YFD0200404-10] and the Shanxi Key Research and Development Program [grant number 201803D221005-1].The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.