Abstract
Research was initiated in 1993 to determine the N fertilizer requirement for dryland winter wheat ( Triticum aestivum L.) grown under reduced tillage systems in western Kansas. Six sites in west‐central Kansas were selected each year for 4 yr in cooperation with area farmers. The typical cropping system was wheat‐fallow with reduced tillage practices. All sites were on silt loam soil that ranged in residual soil nitrate‐N content from 2 to 9 mg kg −1 (0‐ to 60‐cm sample). Crop residue cover at wheat planting averaged 28%. Fluid N (28% N as urea‐ammonium nitrate solution, UAN) was injected in the fall and spring and surface broadcast during the winter and spring at five rates (22, 45, 67, 90, and 112 kg ha −1 ) along with a zero N control. Typical production practices consisted of planting winter wheat in mid‐September with a hoe‐type drill. Grain protein increased linearly with increased N rates with greater than 130 g kg −1 when 112 kg N ha −1 was injected. Apparent fertilizer N recovery decreased with increased N rates, but was consistently higher with fall or spring injected rather than winter or spring broadcast UAN. The straw/yield ratio was greater than 2 across all N rates, which is greater than the commonly used value of 1.7. The soil N test was an indicator of yield response to N fertilization. Grain yields increased in 10 of 13 site‐years with N fertilizer. Average grain yields were 8% greater from spring injected than broadcast UAN. The time of N application had little effect on grain yield. Economic analysis indicated that injecting UAN in the fall or spring was more profitable than topdressing UAN in the winter or spring because of improved yields and/or lower total N costs. These data suggest that N rate recommendations should vary with application method.
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 10
Claim · model-written summary
Grain protein increased linearly with nitrogen rate.
- Taxon
- winter wheat
Triticum aestivumt0 - Treatment
- increased N ratese0
- Outcome
- Grain proteine0
- Direction
- increasede0
- Value
- greater than 130 g kg −1e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Grain protein increased linearly with increased N rates with greater than 130 g kg −1 when 112 kg N ha −1 was injected.”
t0“Winter Wheat”
Claim · model-written summary
Apparent fertilizer nitrogen recovery fell as nitrogen rate increased.
- Taxon
- winter wheatTriticum aestivumt0
- Treatment
- increased N ratese0
- Outcome
- Apparent fertilizer N recoverye0
- Direction
- decreasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Apparent fertilizer N recovery decreased with increased N rates”
t0“Winter Wheat”
Claim · model-written summary
Injected UAN gave higher fertilizer nitrogen recovery than broadcast UAN.
- Taxon
- winter wheatTriticum aestivumt0
- Treatment
- fall or spring injectede0
- Outcome
- fertilizer N recoverye1
- Direction
- highere0
- Comparator
- winter or spring broadcast UANe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“was consistently higher with fall or spring injected rather than winter or spring broadcast UAN.”
t0“Winter Wheat”
e1“Apparent fertilizer N recovery decreased with increased N rates, but was consistently higher with fall or spring injected rather than winter or spring broadcast UAN.”
Claim · model-written summary
The straw to yield ratio exceeded two at every nitrogen rate.
- Taxon
- winter wheatTriticum aestivumt0
- Outcome
- straw/yield ratioe0
- Direction
- greater thane0
- Value
- greater than 2e0
- Comparator
- commonly used value of 1.7e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The straw/yield ratio was greater than 2 across all N rates, which is greater than the commonly used value of 1.7.”
t0“Winter Wheat”
Claim · model-written summary
The soil nitrogen test indicated wheat yield response to fertilization.
- Taxon
- winter wheatTriticum aestivumt0
- Outcome
- yield response to N fertilizatione0
- Setting
- soil N teste0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The soil N test was an indicator of yield response to N fertilization.”
t0“Winter Wheat”
Claim · model-written summary
Nitrogen fertilizer increased grain yield in 10 of 13 site-years.
- Taxon
- winter wheatTriticum aestivumt0
- Treatment
- N fertilizere0
- Outcome
- Grain yieldse0
- Direction
- increasede0
- Value
- 10 of 13 site‐yearse0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Grain yields increased in 10 of 13 site‐years with N fertilizer.”
t0“Winter Wheat”
Claim · model-written summary
Spring injection gave 8% greater grain yield than broadcast UAN.
- Taxon
- winter wheatTriticum aestivumt0
- Treatment
- spring injectede0
- Outcome
- Average grain yieldse0
- Direction
- greatere0
- Value
- 8%e0
- Comparator
- broadcast UANe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Average grain yields were 8% greater from spring injected than broadcast UAN.”
t0“Winter Wheat”
Claim · model-written summary
Nitrogen application timing had little effect on yield.
- Taxon
- winter wheatTriticum aestivumt0
- Treatment
- time of N applicatione0
- Outcome
- grain yielde0
- Direction
- little effecte0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The time of N application had little effect on grain yield.”
t0“Winter Wheat”
Claim · model-written summary
Fall or spring UAN injection was more profitable than winter or spring topdressing.
- Taxon
- winter wheatTriticum aestivumt0
- Treatment
- injecting UAN in the fall or springe0
- Outcome
- profitablee0
- Direction
- more profitablee0
- Comparator
- topdressing UAN in the winter or springe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“injecting UAN in the fall or spring was more profitable than topdressing UAN in the winter or spring”
t0“Winter Wheat”
Claim · model-written summary
The authors recommend varying nitrogen rate recommendations by application method.
- Taxon
- winter wheatTriticum aestivumt0
- Outcome
- N rate recommendations should vary with application methode0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“N rate recommendations should vary with application method.”
t0“Winter Wheat”
The same questions in other papers
nitrogen · quality: protein · Triticum aestivum (wheat)Positive and negative results
399 papers in the same direction as this paper · 47 in the opposite direction · 7 reporting no difference from an alternative
- positive
- negative
- no effect
450 papers more in this group
See all 454 papers →nitrogen · yield · Triticum aestivum (wheat)Positive and negative results
323 papers in the same direction as this paper · 1,737 in the opposite direction
- positive
- positive
- positive
2,057 papers more in this group
See all 2,061 papers →fertilization · yield · Triticum aestivum (wheat)Positive and negative results
3,114 papers in the same direction as this paper · 284 in the opposite direction · 39 reporting no difference from an alternative
- positive
- no effect
- negative
3,434 papers more in this group
See all 3,438 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.