Abstract
Long-term research shows that phosphorus (P) and nitrogen (N) fertilizer must be applied to optimize production of irrigated grain sorghum in western Kansas. In 2020, N applied alone increased yields 60 bu/a, whereas N and P applied together increased yields up to 83 bu/a. Averaged across the past 10 years, N and P fertilization increased sorghum yields up to 82 bu/a. The application of 160 lb/a N (with P) produced the maximum yield in 2020, which is slightly less than the 10-year average (2011–2020). The application of potassium (K) has had no effect on sorghum yield throughout the study period. The 10-year average grain N content reached a maximum of ~0.7 lb/bu while grain P content reached a maximum of 0.15 lb/bu (0.34 lb P2O5/bu) and grain K content reached a maximum of 0.19 lb/bu (0.23 lb K2O/bu). At the highest N, P, and K rate, apparent fertilizer recovery in the grain was 33% for N, 69% for P, and 40% for K. Nitrogen fertilization increased soil organic matter and decreased soil pH. Phosphorus fertilization tended to maintain or increase soil test P levels.
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Claims 14
Claim · model-written summary
N alone increased 2020 sorghum yield by 60 bu/a.
Not reportedTaxonComparator
Verbatim
e0“N applied alone increased yields 60 bu/a”
Claim · model-written summary
N and P together increased 2020 sorghum yield by up to 83 bu/a.
Not reportedTaxonComparator
Verbatim
e0“N and P applied together increased yields up to 83 bu/a”
Claim · model-written summary
Over ten years, N and P fertilization increased sorghum yield by up to 82 bu/a.
SorghumNot reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“N and P fertilization increased sorghum yields up to 82 bu/a”
Claim · model-written summary
160 lb/a N with P produced the highest yield in 2020.
Not reportedTaxonComparator
Verbatim
e0“The application of 160 lb/a N (with P) produced the maximum yield in 2020”
Claim · model-written summary
Potassium application had no effect on sorghum yield during the study.
- Treatment
- potassium (K)e0
- Outcome
- sorghum yielde0
- Direction
- no effecte0
- Qualifier
- throughout the study periode0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The application of potassium (K) has had no effect on sorghum yield throughout the study period”
Claim · model-written summary
Ten-year average grain N content reached about 0.7 lb/bu.
Not reportedTaxon
Verbatim
e0“grain N content reached a maximum of ~0.7 lb/bu”
Claim · model-written summary
Ten-year average grain P content reached 0.15 lb/bu.
Not reportedTaxon
Verbatim
e0“grain P content reached a maximum of 0.15 lb/bu (0.34 lb P2O5/bu)”
Claim · model-written summary
Ten-year average grain K content reached 0.19 lb/bu.
Not reportedTaxon
Verbatim
e0“grain K content reached a maximum of 0.19 lb/bu (0.23 lb K2O/bu)”
Claim · model-written summary
At the highest fertilizer rates, grain recovered 33% of N fertilizer.
Not reportedTaxon
Verbatim
e0“At the highest N, P, and K rate, apparent fertilizer recovery in the grain was 33% for N”
Claim · model-written summary
At the highest fertilizer rates, grain recovered 69% of P fertilizer.
Not reportedTaxon
Verbatim
e0“At the highest N, P, and K rate, apparent fertilizer recovery in the grain was 33% for N, 69% for P”
Claim · model-written summary
At the highest fertilizer rates, grain recovered 40% of K fertilizer.
Not reportedTaxon
Verbatim
e0“At the highest N, P, and K rate, apparent fertilizer recovery in the grain was 33% for N, 69% for P, and 40% for K”
Claim · model-written summary
N fertilization increased soil organic matter.
Not reportedTaxonComparator
Verbatim
e0“Nitrogen fertilization increased soil organic matter”
Claim · model-written summary
N fertilization decreased soil pH.
Not reportedTaxonComparator
Verbatim
e0“Nitrogen fertilization increased soil organic matter and decreased soil pH”
Claim · model-written summary
P fertilization tended to maintain or increase soil test P levels.
Not reportedTaxonComparator
Verbatim
e0“Phosphorus fertilization tended to maintain or increase soil test P levels”
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