Abstract
Abstract The positive effect of placing N (especially NH + 4 ‐N) with P on crop growth has been demonstrated many times in short‐term greenhouse studies. Under field conditions, however, the effect has not been well defined. The present objective was to evaluate N and P placement methods on the P nutrition and final grain yield of wheat ( Triticum aestivum L.) grown in the field and greenhouse. Anhydrous ammonia (NH 3 ), urea‐ammonium nitrate solution (UAN), and sodium nitrate (SN) were N sources while liquid ammonium polyphosphate (APP) was the P source. Methods of N‐P application included: knife N‐knife P (‘dual knife’), knife N‐hroadcast P, broadcast N‐knife P, and broadcast N‐broadcast P. Two nitrification inhibitors were included in some studies. In the greenhouse, APP was labelled with 33 P orthophosphate and 32 P pyrophosphate to examine P uptake of its ortho‐ and polyphosphate fractions with different N‐P‐K application methods each with either a NH + 4 ‐N or NO ‐ 3 ‐N source. Dual knife N‐P applications gave higher leaf P concentrations and grain yields than other N‐P application methods in many of the field studies when ammoniacal N sources were used. Sodium nitrate dual knife applications were not as effective as dual knife applications of UAN or ammonia. The inclusion of the nitrification inhibitor nitrapyrin to dual knife treatments increased grain yield and/or leaf tissue P level in two 1978 studies, but had no effect in 1979. In the greenhouse the highest leaf P levels resulted from the banded NH 3 ‐APP application. The banded SN‐APP application gave the second highest P uptake. This study also demonstrated that the N and APP need to be placed together, not separately in the soil. The amounts of the initial ortho‐ and polyphosphate portions of the APP absorbed by the plants seemed to be a function of fertilizer P demand and not related to fertilizer N in the same band. Including KCl in a band of APP did not affect leaf tissue P concentrations.
Abstract from the paper’s OpenAlex record, shown for indexing and research. Copyright remains with the authors or the publisher. Read at the source ↗
The text the model read, with the source record’s inline markup (italics, sub- and superscripts) rendered and its character entities decoded; quote offsets refer to the raw text.
Claims 11
Claim · model-written summary
Dual knife N-P placement with ammoniacal N raised leaf P concentration in many field studies.
- Taxon
- wheat
Triticum aestivumt0 - Treatment
- Dual knife N‐P applicationse0
- Outcome
- leaf P concentrationse0
- Direction
- highere0
- Qualifier
- when ammoniacal N sources were usede0
- Comparator
- other N‐P application methodse0
- Setting
- field studiese0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Dual knife N‐P applications gave higher leaf P concentrations and grain yields than other N‐P application methods in many of the field studies when ammoniacal N sources were used.”
t0“wheat ( Triticum aestivum L.)”
Claim · model-written summary
Dual knife N-P placement with ammoniacal N raised grain yield in many field studies.
- Taxon
- wheatTriticum aestivumt0
- Treatment
- Dual knife N‐P applicationse0
- Outcome
- grain yieldse0
- Direction
- highere0
- Qualifier
- when ammoniacal N sources were usede0
- Comparator
- other N‐P application methodse0
- Setting
- field studiese0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Dual knife N‐P applications gave higher leaf P concentrations and grain yields than other N‐P application methods in many of the field studies when ammoniacal N sources were used.”
t0“wheat ( Triticum aestivum L.)”
Claim · model-written summary
Sodium nitrate dual knife placement was less effective than UAN or ammonia placement.
- Taxon
- wheatTriticum aestivumt0
- Treatment
- Sodium nitrate dual knife applicationse0
- Outcome
- not as effectivee0
- Direction
- not as effectivee0
- Comparator
- dual knife applications of UAN or ammoniae0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Sodium nitrate dual knife applications were not as effective as dual knife applications of UAN or ammonia.”
t0“wheat ( Triticum aestivum L.)”
Claim · model-written summary
Nitrapyrin increased grain yield and/or leaf P in two 1978 studies.
- Taxon
- wheatTriticum aestivumt0
- Treatment
- nitrapyrine0
- Outcome
- grain yield and/or leaf tissue P levele0
- Direction
- increasede0
- Qualifier
- two 1978 studiese0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The inclusion of the nitrification inhibitor nitrapyrin to dual knife treatments increased grain yield and/or leaf tissue P level in two 1978 studies, but had no effect in 1979.”
t0“wheat ( Triticum aestivum L.)”
Claim · model-written summary
Nitrapyrin had no effect in 1979.
- Taxon
- wheatTriticum aestivumt0
- Treatment
- nitrapyrine0
- Outcome
- grain yield and/or leaf tissue P levele0
- Direction
- no effecte0
- Qualifier
- in 1979e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The inclusion of the nitrification inhibitor nitrapyrin to dual knife treatments increased grain yield and/or leaf tissue P level in two 1978 studies, but had no effect in 1979.”
t0“wheat ( Triticum aestivum L.)”
Claim · model-written summary
Banded NH3-APP gave the highest greenhouse leaf P level.
- Taxon
- wheatTriticum aestivumt0
- Treatment
- banded NH 3 ‐APP applicatione0
- Outcome
- leaf P levelse0
- Direction
- higheste0
- Setting
- greenhousee0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“In the greenhouse the highest leaf P levels resulted from the banded NH 3 ‐APP application.”
t0“wheat ( Triticum aestivum L.)”
Claim · model-written summary
Banded SN-APP gave the second highest P uptake.
- Taxon
- wheatTriticum aestivumt0
- Treatment
- banded SN‐APP applicatione0
- Outcome
- P uptakee0
- Direction
- second higheste0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The banded SN‐APP application gave the second highest P uptake.”
t0“wheat ( Triticum aestivum L.)”
Claim · model-written summary
N and APP needed to be placed together in soil.
- Taxon
- wheatTriticum aestivumt0
- Outcome
- N and APP need to be placed together, not separately in the soile0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“This study also demonstrated that the N and APP need to be placed together, not separately in the soil.”
t0“wheat ( Triticum aestivum L.)”
Claim · model-written summary
Absorption of initial APP ortho- and polyphosphate portions appeared dependent on fertilizer P demand.
- Taxon
- wheatTriticum aestivumt0
- Treatment
- fertilizer P demande0
- Outcome
- amounts of the initial ortho‐ and polyphosphate portions of the APP absorbed by the plantse0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The amounts of the initial ortho‐ and polyphosphate portions of the APP absorbed by the plants seemed to be a function of fertilizer P demand and not related to fertilizer N in the same band.”
t0“wheat ( Triticum aestivum L.)”
Claim · model-written summary
Absorption of initial APP ortho- and polyphosphate portions was not related to N in the same band.
- Taxon
- wheatTriticum aestivumt0
- Treatment
- fertilizer N in the same bande0
- Outcome
- amounts of the initial ortho‐ and polyphosphate portions of the APP absorbed by the plantse0
- Direction
- not relatede0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The amounts of the initial ortho‐ and polyphosphate portions of the APP absorbed by the plants seemed to be a function of fertilizer P demand and not related to fertilizer N in the same band.”
t0“wheat ( Triticum aestivum L.)”
Claim · model-written summary
KCl in an APP band did not affect leaf P concentrations.
- Taxon
- wheatTriticum aestivumt0
- Treatment
- Including KCl in a band of APPe0
- Outcome
- leaf tissue P concentrationse0
- Direction
- did not affecte0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Including KCl in a band of APP did not affect leaf tissue P concentrations.”
t0“wheat ( Triticum aestivum L.)”
The same questions in other papers
nitrapyrin · yield · Triticum aestivum (wheat)Results differ
7 papers in the same direction as this paper · 2 in the opposite direction
- no effect
- no effect
- positive
6 papers more in this group
See all 10 papers →ammonium polyphosphate · nutrient: content · Triticum aestivum (wheat)Positive and negative results
2 in the opposite direction
- positive
- positive
potassium chloride · nutrient: content · Triticum aestivum (wheat)Positive and negative results
2 papers in the same direction as this paper · 5 in the opposite direction
- positive
- positive
- positive
4 papers more in this group
See all 8 papers →Claims are grouped by organism, treatment and what was measured or targeted. A paper counts as positive when any of its claims in the group is positive.