Evaluation of Polymer‐Coated Urea and Urease Inhibitor for Winter Wheat in Southern Alberta
Bibliographic record
Abstract
Nitrogen fertilization of winter wheat ( Triticum aestivum L.) in the drier regions of the Canadian prairies is currently accomplished by banding urea or anhydrous ammonia at seeding or broadcasting urea in early spring. This study was conducted to determine if the efficacy of urea could be improved by using polymer‐coated urea (PCU) or treatment with urease inhibitor N‐( n ‐butyl) thiophosphoric triamide (NBPT). Two field experiments were conducted for 3 yr on wheat stubble and on fallow at Bow Island and at Lethbridge. Grain yield and protein concentration response of winter wheat was determined for noncoated urea (NCU) and PCU banded in the soil at seeding at seven rates from 30 to 210 kg N ha −1 (Exp. 1) and for four N fertilizer types broadcast on the soil surface in early spring at rates of 30, 60, and 90 kg N ha −1 (Exp. 2): NCU, ammonium nitrate (AN), NBPT‐treated urea (NTU), and PCU. When N fertilizer was banded at seeding, grain yield was higher for PCU than NCU, but differences were small (<100 kg ha −1 , <5%) and likely not due to reduced N losses. Grain protein concentration was unaffected by fertilizer type. When N fertilizer was broadcast on the soil surface in the spring, grain yield and protein concentration were similar for NCU, AN, and NTU, but reduced for PCU due to excessive delay in N release. The negligible impact of polymer coating or treatment with NBPT on urea efficacy reflects the low risk of urea N loss in this region.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".