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ORIGINAL RESEARCH
Comparative Efficacy of Coated Diammonium
Phosphate Formulations for Improving Crop
Productivity and Nutrient Uptake in Maize
1
Department of Soil Science, The Islamia University of Bahawalpur, 63100, Bahawalpur, Pakistan
2
Department of Agronomy, The Islamia University of Bahawalpur 63100, Pakistan
3
Department of Life Sciences, Western Caspian University, Baku, Azerbaijan
4
Department of Genetics and Bioengineering, Faculty of Engineering and Natural Sciences, International University
of Sarajevo, 71210 Sarajevo, Bosnia and Herzegovina
5
Department of Botany and Microbiology, College of Science, King Saud University, Riyadh 11451, Saudi Arabia
Submission date: 2024-02-29
Final revision date: 2024-03-20
Acceptance date: 2024-04-26
Online publication date: 2024-12-30
Publication date: 2025-01-28
Corresponding author
Azhar Hussain
Department of Soil Science, The Islamia University of Bahawalpur, 63100, Bahawalpur, Pakistan
Department of Soil Science, The Islamia University of Bahawalpur, 63100, Bahawalpur, Pakistan
Pol. J. Environ. Stud. 2025;34(3):3231-3241
KEYWORDS
TOPICS
ABSTRACT
Fertilizer use efficiency is the major problem behind low crop productivity on calcareous sandy loam
soils, mostly for exhaustive crops like maize. Improving maize productivity to meet food requirements is
among the priority research areas for scientists. The study explores the efficacy of coated diammonium
phosphate (DAP) with phosphate solubilizing bacteria (PSB) and their extracted metabolites to improve
maize growth and soil health. For this purpose, the efficacy of conventional DAP is compared with that
of coated DAP (C-DAP) to improve soil nutrient dynamics, maize seedling growth, the antioxidant
system, and nutrient uptake in grains. Results showed that C-DAP significantly improved maize growth
as compared to uncoated DAP. Bacterial and metabolites coated DAP formulations exhibit increased soil
available phosphorus by 44% and 41% and extractable potassium by 41% and 43%, respectively, at 100%
of the required P dose. Coated DAP treatments also enhanced microbial biomass carbon in rhizospheric
soil, indicating a positive influence on soil microbial communities. Furthermore, bacterial and metabolites
coated DAP formulations enhanced relative water contents (44% and 40%), membrane stability index
(45% and 47%), and chlorophyll contents (37% and 39%), respectively. The present findings conclude
that the use of microbial and metabolites coated DAP is an effective strategy to improve maize growth,
physiology, and nutrient use efficiency in a sustainable manner to address food security.
CONFLICT OF INTEREST
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
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