Maize Trial with Puraloop in Germany
4
Weihenstephan-Triesdorf 2024
4
Key Conclusions
Puraloop® stands out as a highly efficient phosphorus fertilizer. It performs comparably to TSP in terms of growth, uptake, and biomass increase. While it shows a slightly lower immediate fertilizing effect, its unique formulation ensures that phosphorus is released more gradually, enhancing overall efficiency. This slower release allows plants to take up phosphorus more effectively, leveraging the strongest competitive forces in the soil. Consequently, Puraloop® provides plants with a sustained and efficient phosphorus supply, promoting healthier and more robust growth over time.
Objective
As part of the trial, the P fertilization effect of Puraloop® (P38) and Coated-TSP (TSPC) were tested in comparison to triple superphosphate (TSP) in a pot trial with maize at the Weihenstephan-Triesdorf University of Applied Sciences. Maize was selected for this trial because it is a heavy feeder that clearly reacts to poor P supply.
A silty loam with a low pH value (soil pH 5.1) and a sandy loam with a higher pH value (soil pH 7.2) were used as test soils. The soils were additionally fertilized with nitrogen, potassium, magnesium and trace elements.
Trial Details
Trial station
Weihenstephan-Triesdorf
Crop
Maize
Product
PURALOOP® 0-38-0
Assessments
Fresh matter, dry matter, P-uptake
Treatments
The analyses of the total P content (wet digestion under pressure with HNO₃/H₂O₂) resulted in the following treatments for two soils in the trial:
Control, no phosphorus
Puraloop® 36.2 % total P₂O₅
TSP 47.0 % total P₂O₅
The following soil situations were simulated in the pots:
Soil type | pH (CaCl₂) | P₂O₅ (*CAL) | K₂O (*CAL) | MgO (*CaCl₂) |
---|---|---|---|---|
1/silty loam | 5.1 | 8 | 70 | 345 |
2/sandy loam | 7.2 | 19 | 65 | 142 |
*in mg/kg of soil
Treatments
The analyses of the total P content (wet digestion under pressure with HNO₃/H₂O₂) resulted in the following treatments for two soils in the trial:
Control, no phosphorus
Puraloop® 36.2 % total P₂O₅
TSP 47.0 % total P₂O₅
The following soil situations were simulated in the pots:
Soil type | pH (CaCl₂) | P₂O₅ (*CAL) | K₂O (*CAL) | MgO (*CaCl₂) |
---|---|---|---|---|
1/silty loam | 5.1 | 8 | 70 | 345 |
2/sandy loam | 7.2 | 19 | 65 | 142 |
*in mg/kg of soil
Results
The trial showed the following results with regard to P uptake and yield:
The P use efficiency, or P fertilizer efficiency, of TSP is slightly lower than Puraloop.
Differences in growth
No visual differences during growth due to P fertilization on both the soils and both pH values.
The following bar chart shows the P uptake in the treatments:
- Regardless of the soil pH value, Puraloop® has a significant P fertilization effect, which is only slightly lower with Puraloop® than with TSP.
- On average over both soils, the phosphorus utilization efficiency of Puraloop® was 9.9 (± 0.3) %. TSP was 10.7 (± 0.4) % and did not differ significantly from either of the other two treatments.
- In the soil with pH 5, no significant differences in the P uptake of the plants can be seen.
- In soil with pH 7.2, there were no significant differences in uptake between the Puraloop® and TSP fertilizer variants, where TSP values were only slightly higher.
- Significantly more phosphate is extracted from the soil with a low pH value with TSP than with Puraloop®. In soil with a higher pH value, the quantities for Puraloop® and TSP are relatively comparable.