Evidence map›Paper›PMID 41629802›Full record

ArticleBMC plant biology2026

Effects of different types of acidic nitrogen-enriched biochar on spinach growth, nitrogen use efficiency, and chemical properties of calcareous sandy soil.

Amal S M Gad El-Hak, Abu El-Eyuoon Abu Zied Amin, Muhammad Abdel-Shakour, Abdalrahman G Algamal, Refaat M Mahfouz

Abstract read
In one paragraph

Article in BMC plant biology, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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0citing papers in PubMed
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1 · What the graph read from it

What it found

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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

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3 · Its place in the literature

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No citing paper in PubMed yet.

4 · The record

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PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

5 authors.

Amal S M Gad El-HakChemistry Department, Faculty of Science, Assiut University, Assiut, P.O. Box: 71526, Egypt.
Abu El-Eyuoon Abu Zied AminSoils and Water Department, Faculty of Agriculture, Assiut University, P.O. Box: 71526, Assiut, Egypt. abueleyuoon.amin@aun.edu.eg.
Muhammad Abdel-ShakourChemistry Department, Faculty of Science, Assiut University, Assiut, P.O. Box: 71526, Egypt.
Abdalrahman G AlgamalEgyptian Petroleum Research Institute, Cairo, Egypt.
Refaat M MahfouzChemistry Department, Faculty of Science, Assiut University, Assiut, P.O. Box: 71526, Egypt.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundEnriching biochar with nitrogen and using it as a slow-release nitrogen fertilizer is a promising strategy to avoid excessive use of chemical nitrogen fertilizers. Therefore, this study investigated the effect of different types of nitrogen-enriched biochar on the soil’s chemical properties, nitrogen use efficiency (NUE), and growth of spinach in calcareous sandy soil. This pot experiment included 9 treatments: control (unamended soil, CK), willow branches biochar (WB), apple of Sodom biochar (ASB), marvel grass biochar (MB), halfa grass biochar (HB), nitrogen-enriched willow branches biochar (NEWB), nitrogen-enriched apple of Sodom (NEASB), nitrogen-enriched marvel grass biochar (NEMB), nitrogen-enriched halfa grass biochar (NEHB). Nitrogen-enriched biochar and biochar were added at a level of 5 g kg− 1 soil. This experiment was conducted on the spinach plant.

resultsSoil available nitrate increased significantly with adding NEHB, NEMB, NEWB, and NEASB compared to the control treatment. Adding HB, NEHB, NEMB, NEWB, and NEASB to the soil significantly improved the fresh and dry shoot of the spinach plant compared to the control. Applying HB, NEHB, NEMB, NEWB, and NEASB treatments increased the fresh shoot of the spinach plant over the control by ~ 62%, 245%, 237%, 275%, and 196%, respectively. On the other hand, adding MB, WB, and ASB treatments decreased the fresh shoot of the spinach plant relative to the control by ~ 14%, 3%, and 14%, respectively. Applying different types of nitrogen-enriched biochar significantly improved the NUE of spinach plant compared to the original biochar treatments.

conclusionsOur results suggest that nitrogen-enriched biochar can be a promising strategy in sustainable agriculture to increase soil nutrient availability, improve spinach growth, and enhance nitrogen use efficiency in spinach. Nitrogen-enriched biochar can serve as an effective and cost-efficient alternative to chemical nitrogen fertilizers.

Indexed as

CharcoalNitrogenSoilSpinacia oleraceaFertilizersNitratesSandbiocharCharcoalFertilizersNitratesNitrogenSandSoilAvailable nitrateAvailable potassiumChlorophyllNitrogen-enriched biocharNitrogen use efficiency

Identifiers

PMID41629802
PMCPMC12931089

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.