Agronomic evaluation of a homogenous nitrogen-phosphorus-sulphur fertilizer in southern Manitoba
Notice bibliographique
Résumé
Field studies and a growth chamber study were conducted to evaluate the effect of a homogeneous nitrogen-phosphorus-sulphur (NPS) fertilizer on the emergence and crop utilization of phosphorus (P) and sulphur (S). In the field study, spring wheat (Triticum aestivum L. cv. AC Barrie) and spring canola (Brassica napus L. cv. DKL 34-55) were grown in southern Manitoba and fertilized with NPS, monoammonium phosphate (MAP) + ammonium sulphate (AS), MAP + elemental S-bentonite (So), MAP only and a control (no P or S); and S was applied at 0,5, 10, 15 and 20 kg ha-1. Wheat and canola emergence was not affected by any of the seed-placed P and S fertilizer sources or S rates used in the study. The NPS and other P fertilizer sources increased dry matter yield 6 - 10% in wheat at midseason but not at maturity; canola yields were not increased by P and S fertilization at any stage. At midseason, all of the phosphate fertilizers increased P uptake by 8 - 13% in wheat and 23 - 45% in canola, while NPS and MAP + AS increased S uptake by wheat 7 - 9 %. At maturity, all of the P fertilizers increased total P uptake by 9 - 12% in wheat but not in canola, and all responses to S fertilization had disappeared. To determine the availability of P, SO4 and So in NPS fertilizer, two S-deficient soils were used for a growth chamber study. Spring canola was fertilized with NPS, MAP + AS, MAP + So, MAP only, AS only and a control (no P or S). At 45 days after emergence, the canola was harvested and dry matter yield, P and S uptake were measured. After this harvest, the soils were incubated to simulate potential So oxidation conditions between cropping seasons in Manitoba. The pots were then replanted to a second crop of canola to measure residual P and S supplied by NPS fertilizer. In the first canola crop, dry matter yield and apparent P fertilizer use efficiency of NPS fertilizer was 75% and 81% of that for MAP + AS respectively. The apparent S fertilizer use efficiency for NPS was 35% of that for MAP + AS. When the second crop was grown without P and S fertilization, dry matter and residual P and S uptake were highest for the NPS treatment; however, the cumulative dry matter yield (crop 1 + 2) produced with NPS fertilizer was 83% of that for MAP + AS. The apparent P fertilization efficiencies for MAP + AS and NPS fertilizers were 54 - 56% over the two cropping periods. However, the apparent S fertilizer use efficiency of NPS fertilizer was approximately 50% lower than MAP + AS. Overall, the studies indicated that NPS fertilizer was not detrimental to wheat and canola emergence at the rates used in the study; the availability of P from NPS fertilizer appeared to be at least equivalent to MAP; and that only the SO4-S portion of NPS fertilizer appeared to be available to crops, with no measurable amount of oxidation of the So-S portion.
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Comment cette classification a été obtenuedéplier
Prédiction machine sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Le volet Gemma est une étiquette directe du modèle pour chaque travail de la base, lue sur la notice réduite au titre. Le volet Codex est un classifieur appris des 10 348 étiquettes directes de Codex et calibré sur les taux pondérés de l'échantillon; les champs sans appui suffisant ne portent aucun appel Codex. Le mode candidate est l'union des deux volets; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont pas des étiquettes humaines.
Scores du classifieur distillé par catégorie (deux têtes)
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,000 | 0,001 |
| Études des sciences et des technologies | 0,001 | 0,000 |
| Communication savante | 0,000 | 0,000 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,001 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule source (Gemma direct ou Codex distillé), pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».