Abstract
Core Ideas Nitrogen applications increased soybean yields by 4% for sandy/silt loam soil. Nitrogen applications increased soybean yields by 8% for clay soil. Yield components response to N applications parallels the trends observed for yield. Nitrogen application is not an economically feasible way to improve soybean yield. Trials were conducted in 2014 and 2015 at Delta Research and Extension Center in Stoneville, MS, to evaluate soybean [ Glycine max (L.) Merr.] response to N sources (ammonium sulfate [AMS], polymer‐coated urea [PCU], urea+urease inhibitor [Urea+NBPT, N‐(n‐butyl) thiophosphoric triamide]), N application rate (0, 45, 90, 135, 179 kg N ha −1 ) and timing (V4, R1), on two soil textures (sandy/silt loam and clay) that are commonly used for soybean production in Mississippi. Urea+NBPT produced 5 and 8% greater aboveground biomass than AMS and PCU on sandy/silt loam soil. Nitrogen applications at the V4 growth stage resulted in 6% greater biomass production than the R1 application timing on sandy/silt loam. Averaged over N rates where a seed yield increase was observed, N applications increased soybean yields by 4% for sandy/silt loam soil and by 8% for clay soil compared to unfertilized soybeans. No differences were observed for soybean yields between N rates of 45, 90, 135, and 179 kg N ha −1 . Soybean yield from PCU was 2.5% greater than urea+NBPT on sandy/silt loam soil. Nitrogen rates influenced soybean yield components including pods and seeds plant −1 on sandy/silt loam soil as well as seeds and seed mass plant −1 on clay soil. Yield component response to N fertilization parallels the trends observed with overall soybean seed yield increases on both soil textures. Despite increases in seed yield observed with N application, analysis of partial returns suggests that N application is not an economically feasible way to improve soybean seed yield.
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Claims 10
Claim · model-written summary
N applications increased soybean yields by 4% on sandy/silt loam soil compared with unfertilized soybeans.
- Taxon
- soybean
Glycine maxe1 - Treatment
- N applicationse1
- Outcome
- soybean yieldse1
- Direction
- increasede1
- Value
- 4%e1
- Comparator
- unfertilized soybeanse1
- Setting
- sandy/silt loam soile1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“Averaged over N rates where a seed yield increase was observed, N applications increased soybean yields by 4% for sandy/silt loam soil and by 8% for clay soil compared to unfertilized soybeans”
Claim · model-written summary
N applications increased soybean yields by 8% on clay soil compared with unfertilized soybeans.
- Taxon
- soybeanGlycine maxe1
- Treatment
- N applicationse1
- Outcome
- soybean yieldse1
- Direction
- increasede1
- Value
- 8%e1
- Comparator
- unfertilized soybeanse1
- Setting
- clay soile1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“Averaged over N rates where a seed yield increase was observed, N applications increased soybean yields by 4% for sandy/silt loam soil and by 8% for clay soil compared to unfertilized soybeans”
Claim · model-written summary
Urea+NBPT produced 5% greater aboveground biomass than AMS on sandy/silt loam soil.
- Taxon
- soybeanGlycine maxe0
- Treatment
- Urea+NBPTe1
- Outcome
- aboveground biomasse1
- Direction
- greatere1
- Value
- 5e1
- Comparator
- AMSe1
- Setting
- sandy/silt loam soile1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Trials were conducted in 2014 and 2015 at Delta Research and Extension Center in Stoneville, MS, to evaluate soybean”
e1“Urea+NBPT produced 5 and 8% greater aboveground biomass than AMS and PCU on sandy/silt loam soil”
Claim · model-written summary
Urea+NBPT produced 8% greater aboveground biomass than PCU on sandy/silt loam soil.
- Taxon
- soybeanGlycine maxe0
- Treatment
- Urea+NBPTe1
- Outcome
- aboveground biomasse1
- Direction
- greatere1
- Value
- 8%e1
- Comparator
- PCUe1
- Setting
- sandy/silt loam soile1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Trials were conducted in 2014 and 2015 at Delta Research and Extension Center in Stoneville, MS, to evaluate soybean”
e1“Urea+NBPT produced 5 and 8% greater aboveground biomass than AMS and PCU on sandy/silt loam soil”
Claim · model-written summary
N applications at the V4 growth stage gave 6% greater biomass production than the R1 timing on sandy/silt loam soil.
- Taxon
- soybeanGlycine maxe0
- Treatment
- Nitrogen applications at the V4 growth stagee2
- Outcome
- biomass productione2
- Direction
- greatere2
- Value
- 6%e2
- Comparator
- the R1 application timinge2
- Setting
- sandy/silt loame2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Trials were conducted in 2014 and 2015 at Delta Research and Extension Center in Stoneville, MS, to evaluate soybean”
e2“Nitrogen applications at the V4 growth stage resulted in 6% greater biomass production than the R1 application timing on sandy/silt loam”
Claim · model-written summary
No differences in soybean yields were observed between N rates of 45, 90, 135 and 179 kg N ha −1.
- Taxon
- soybeanGlycine maxe3
- Treatment
- N ratese3
- Outcome
- soybean yieldse3
- Direction
- No differencese3
- Comparator
- 45, 90, 135, and 179 kg N ha −1e3
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e3“No differences were observed for soybean yields between N rates of 45, 90, 135, and 179 kg N ha −1”
Claim · model-written summary
Soybean yield from PCU was 2.5% greater than from urea+NBPT on sandy/silt loam soil.
- Taxon
- SoybeanGlycine maxe4
- Treatment
- PCUe4
- Outcome
- yielde4
- Direction
- greatere4
- Value
- 2.5%e4
- Comparator
- urea+NBPTe4
- Setting
- sandy/silt loam soile4
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e4“Soybean yield from PCU was 2.5% greater than urea+NBPT on sandy/silt loam soil”
Claim · model-written summary
Nitrogen rates influenced soybean pods and seeds per plant on sandy/silt loam soil.
- Taxon
- soybeanGlycine maxe5
- Treatment
- Nitrogen ratese5
- Outcome
- pods and seeds plant −1e5
- Setting
- sandy/silt loam soile5
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e5“Nitrogen rates influenced soybean yield components including pods and seeds plant −1 on sandy/silt loam soil as well as seeds and seed mass plant −1 on clay soil”
Claim · model-written summary
Nitrogen rates influenced soybean seeds and seed mass per plant on clay soil.
- Taxon
- soybeanGlycine maxe5
- Treatment
- Nitrogen ratese5
- Outcome
- seeds and seed mass plant −1e5
- Setting
- clay soile5
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e5“Nitrogen rates influenced soybean yield components including pods and seeds plant −1 on sandy/silt loam soil as well as seeds and seed mass plant −1 on clay soil”
Claim · model-written summary
N application is not an economically feasible way to improve soybean seed yield.
- Taxon
- soybeanGlycine maxe6
- Outcome
- economically feasible way to improve soybean seed yielde6
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e6“analysis of partial returns suggests that N application is not an economically feasible way to improve soybean seed yield”
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