Exploratory profiling of soil bacterial communities and fertility in tropical maize amended with diatomaceous earth

Camilo Alexander Mestanza Uquillas; Diana Verónica Véliz Zamora; ángel Virgilio Cedeño Moreira; John Jairo Pinargote Alava

doi:10.18393/ejss.2016780

Exploratory profiling of soil bacterial communities and fertility in tropical maize amended with diatomaceous earth

Abstract

Soil bacterial communities are sensitive indicators of biological condition in tropical agroecosystems, yet field information from acidic maize soils in Ecuador remains scarce. This study provides an exploratory profile of soil bacterial communities and fertility indicators in maize amended with diatomaceous earth under field conditions. A randomized complete block field experiment was established with three treatments and five replications: untreated control without fertilization or diatomaceous earth (T1), conventional fertilization (T2), and conventional fertilization plus diatomaceous earth (T3). Grain yield was measured from replicated plots, whereas soil chemistry and 16S rRNA bacterial profiles were obtained from composite analytical profiles and interpreted descriptively. One composite baseline soil profile was obtained before treatment differentiation, and one composite profile per treatment was obtained at 60 and 120 days after sowing. Soil was sampled from the 0-30 cm layer in the inter-row zone. The diatomaceous earth product was applied edaphically at 12 kg ha-1 and contained 73.60% w/w SiO2 according to the product certificate. The 16S rRNA V3-V4 region was sequenced using an Illumina workflow, and raw FASTQ files were deposited in NCBI SRA. Grain yield differed among treatments (F = 18.18; P = 0.0011), with T2 and T3 statistically similar and both higher than T1. Bacterial profiles were dominated by Acidobacteria, Actinobacteria, Proteobacteria, Firmicutes and Verrucomicrobia. T3 at 120 DAS showed the highest numerical Shannon index and provider-reported species-level classifications among treatment-time profiles, but these patterns were not tested inferentially. The study offers a transparent baseline for future replicated microbiome work in tropical acidic maize soils.

Keywords

Thanks

The authors gratefully acknowledge the field and laboratory teams for their assistance with soil sampling, crop management and sample processing, and thank the anonymous reviewers for their constructive comments and suggestions, which helped improve the quality and clarity of the manuscript.

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Details

Primary Language

English

Subjects

Soil Sciences and Plant Nutrition (Other)

Journal Section

Research Article

Authors

Camilo Alexander Mestanza Uquillas ^* This is me
0000-0001-9299-170X
Ecuador

Diana Verónica Véliz Zamora This is me
0000-0003-2039-8741
Ecuador

ángel Virgilio Cedeño Moreira This is me
0000-0002-6564-5569
Ecuador

John Jairo Pinargote Alava This is me
0000-0002-8065-5124
Ecuador

Publication Date

October 5, 2026

Submission Date

June 16, 2026

Acceptance Date

August 7, 2026

Published in Issue

Year 2026 Volume: 15 Number: 4

DOI

https://doi.org/10.18393/ejss.2016780

IZ

https://izlik.org/JA22YE27GX

Cite

RIS / Bibtex

APA

Mestanza Uquillas, C. A., Véliz Zamora, D. V., Cedeño Moreira, ángel V., & Pinargote Alava, J. J. (2026). Exploratory profiling of soil bacterial communities and fertility in tropical maize amended with diatomaceous earth. Eurasian Journal of Soil Science, 15(4), 599-608. https://doi.org/10.18393/ejss.2016780

AMA

1.Mestanza Uquillas CA, Véliz Zamora DV, Cedeño Moreira ángel V, Pinargote Alava JJ. Exploratory profiling of soil bacterial communities and fertility in tropical maize amended with diatomaceous earth. EJSS. 2026;15(4):599-608. doi:10.18393/ejss.2016780

Chicago

Mestanza Uquillas, Camilo Alexander, Diana Verónica Véliz Zamora, ángel Virgilio Cedeño Moreira, and John Jairo Pinargote Alava. 2026. “Exploratory Profiling of Soil Bacterial Communities and Fertility in Tropical Maize Amended With Diatomaceous Earth”. Eurasian Journal of Soil Science 15 (4): 599-608. https://doi.org/10.18393/ejss.2016780.

EndNote

Mestanza Uquillas CA, Véliz Zamora DV, Cedeño Moreira ángel V, Pinargote Alava JJ (October 1, 2026) Exploratory profiling of soil bacterial communities and fertility in tropical maize amended with diatomaceous earth. Eurasian Journal of Soil Science 15 4 599–608.

IEEE

[1]C. A. Mestanza Uquillas, D. V. Véliz Zamora, ángel V. Cedeño Moreira, and J. J. Pinargote Alava, “Exploratory profiling of soil bacterial communities and fertility in tropical maize amended with diatomaceous earth”, EJSS, vol. 15, no. 4, pp. 599–608, Oct. 2026, doi: 10.18393/ejss.2016780.

ISNAD

Mestanza Uquillas, Camilo Alexander - Véliz Zamora, Diana Verónica - Cedeño Moreira, ángel Virgilio - Pinargote Alava, John Jairo. “Exploratory Profiling of Soil Bacterial Communities and Fertility in Tropical Maize Amended With Diatomaceous Earth”. Eurasian Journal of Soil Science 15/4 (October 1, 2026): 599-608. https://doi.org/10.18393/ejss.2016780.

JAMA

1.Mestanza Uquillas CA, Véliz Zamora DV, Cedeño Moreira ángel V, Pinargote Alava JJ. Exploratory profiling of soil bacterial communities and fertility in tropical maize amended with diatomaceous earth. EJSS. 2026;15:599–608.

MLA

Mestanza Uquillas, Camilo Alexander, et al. “Exploratory Profiling of Soil Bacterial Communities and Fertility in Tropical Maize Amended With Diatomaceous Earth”. Eurasian Journal of Soil Science, vol. 15, no. 4, Oct. 2026, pp. 599-08, doi:10.18393/ejss.2016780.

Vancouver

1.Camilo Alexander Mestanza Uquillas, Diana Verónica Véliz Zamora, ángel Virgilio Cedeño Moreira, John Jairo Pinargote Alava. Exploratory profiling of soil bacterial communities and fertility in tropical maize amended with diatomaceous earth. EJSS. 2026 Oct. 1;15(4):599-608. doi:10.18393/ejss.2016780