Page 130 - EER-2-1

Explora: Environment
and Resource Sustainable fertilization for long bean cultivation

soil properties. The increase in soil pH from 5.2 to 5.8 is
particularly noteworthy, as it suggests a reduction in soil
acidity, which is critical for improving nutrient availability
and reducing toxicity from aluminum ions. The organic
matter content doubled from 1.25% to 2.50%, reflecting
the contribution of quail manure in enriching the soil with
organic carbon and enhancing its physical properties. 10,13
The available phosphorus concentration increased
from 8.3 to 18.7 mg/kg, demonstrating the synergistic
effect of organic manure and natural phosphate. Organic
manure enhances microbial activity, which facilitates
phosphorus solubilization from natural phosphate, thereby
improving phosphorus availability in acidic soils, where Figure 2. Effect of treatments on plant growth parameters (days to
fixation is a major constraint. These findings align with flowering and stem diameter; n = 3). Different letters (a-f) indicate
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significant differences at P < 0.05 according to Duncan’s New Multiple
previous studies demonstrating that natural phosphate Range Test. Treatments sharing the same letter are not significantly
amendments can sustain phosphorus release in acidic different from each other.
conditions, preventing fixation and ensuring long-term
nutrient availability to plants. 35,36 Similarly, Manono particularly nitrogen and phosphorus. These nutrients
et al. observed that organic amendments contributed to are essential for vegetative growth and accelerating the
14
increased phosphorus availability in acidic soils, likely due transition to reproductive phases. 30
to their role in enhancing microbial activity and facilitating
phosphorus solubilization. The reduction in aluminum The enhanced availability of phosphorus likely
saturation from 40% to 25% further underscores the supported critical metabolic processes, including
effectiveness of these amendments in mitigating the adenosine triphosphate production, which is necessary for
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adverse effects of soil acidity. Lower aluminum levels flowering initiation. Nitrogen supplied by quail manure
37
reduce phosphorus fixation in the soil matrix, thereby further promoted vigorous vegetative growth, enabling
enhancing phosphorus availability and uptake by plants. 38 the plants to transition to reproductive development more
rapidly. These findings are consistent with those of Míguez-
In addition, bulk density decreased from 1.45 to Montero et al., who reported that balanced nitrogen
40
1.30 g/cm³, indicating improved soil structure and porosity and phosphorus inputs significantly reduced the time to
(P = 0.027). This finding aligns with Manono et al., who flowering in legumes.
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reported that the application of organic amendments
significantly reduced bulk density, improving water Stem diameter, an indicator of plant robustness and
infiltration, retention, and aeration, thereby enhancing nutrient transport efficiency, was significantly affected by
root penetration and overall soil quality. These changes the treatments. The P2R2 treatment yielded the largest
collectively demonstrate the potential of integrating stem diameter (0.86 ± 0.03 cm), which was significantly
organic and natural fertilizers to transform marginal soils higher than all other treatments (P < 0.05). In contrast,
into productive agricultural systems, offering a sustainable the control treatment (P0R0) exhibited the smallest stem
solution for improving soil health in tropical regions. diameter (0.40 ± 0.03 cm), with statistically significant
differences from all fertilized treatments. The increase in
3.2. Effect of treatments on plant growth stem diameter under the P2R2 treatment can be attributed
parameters to the synergistic effects of organic matter and phosphorus
The application of quail manure and natural phosphate in enhancing soil structure and nutrient availability. 41
fertilizers significantly influenced the growth parameters Organic matter provided by quail manure increased soil
of long beans, particularly days to flowering and stem carbon content, which in turn stimulated microbial activity
diameter (Figure 2). The treatments resulted in a notable and improved soil aggregate stability. This enhancement
reduction in days to flowering, with the shortest flowering likely facilitated better root penetration and moisture
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time observed under the P2R2 treatment (27.00 ± retention, allowing for more efficient nutrient uptake.
0.85 days). In contrast, the control (P0R0) exhibited the The slow-release phosphorus from natural phosphate
longest time to flowering (34.66 ± 1.20 days). The reduction contributed to sustained nutrient availability, which
in days to flowering under the P2R2 treatment indicates supported cell division and elongation, resulting in thicker
that the combined application of quail manure and and sturdier stems. The microbial solubilization of
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natural phosphate provided optimal nutrient availability, phosphorus further enhanced its bioavailability, improving

Volume 2 Issue 1 (2025) 5 doi: 10.36922/eer.8348