Abstract
Abstract The effect of N and P fertilization on crop yields under irrigation was evaluated in a nonlegume rotation (barley, corn, potatoes), and in a legume rotation (barley, alfalfa, alfalfa, alfalfa, corn, potatoes), on Gardena loam at Upharn, N. Dak. In the nonlegume rotation all crops responded to N. Phosphorus alone decreased yields of corn forage. However, with adequate N, P increased yields of barley, corn and potatoes. In the legume rotation, the major effect of alfalfa was to supply available N. Added N fertilizer increased the yields of all nonlegume crops, but P additions increased yields of all crops. Phosphorus was available to potatoes 5 years after it had been added on the barley crop. Yields of barley and corn tended to be higher in the legume rotation than in the nonlegume rotation, regardless of the fertilizer treatment. At the highest N fertilizer rate, yields of potatoes were similar in the two rotations. Higher yields in the legume rotation resulted mainly from the available N contributed by the alfalfa, but other factors also appear to be involved. Alfalfa, grown only in the establishing year, contributed available N to the succeeding corn crop in an amount comparable to alfalfa grown for a longer time.
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Claims 10
Claim · model-written summary
In the nonlegume rotation, N fertilization increased yields of all crops.
- Taxon
- barley, corn, potatoes
Solanum tuberosum.jpg?width=60)
Hordeum vulgare
Zea mays subsp. mayse1 - Treatment
- Ne2
- Outcome
- crop yieldse1
- Direction
- increaseinferrede1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
.jpg?width=500)
Verbatim
e1“The effect of N and P fertilization on crop yields under irrigation was evaluated in a nonlegume rotation (barley, corn, potatoes)”
e2“In the nonlegume rotation all crops responded to N”
Claim · model-written summary
Phosphorus alone decreased yields of corn forage in the nonlegume rotation.
- Taxon
- cornZea mays subsp. mayse3
- Treatment
- Phosphorus alonee3
- Outcome
- yields of corn foragee3
- Direction
- decreasede3
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e3“Phosphorus alone decreased yields of corn forage”
Claim · model-written summary
With adequate N, P increased yields of barley, corn and potatoes.
- Taxon
- barley, corn and potatoesSolanum tuberosumHordeum vulgareZea mays subsp. mayse4
- Treatment
- Pe4
- Outcome
- yieldse4
- Direction
- increasede4
- Qualifier
- with adequate Ne4
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e4“However, with adequate N, P increased yields of barley, corn and potatoes”
Claim · model-written summary
Added N fertilizer increased yields of all nonlegume crops in the legume rotation.
Not reportedComparator
Verbatim
e5“Added N fertilizer increased the yields of all nonlegume crops”
Claim · model-written summary
P additions increased yields of all crops in the legume rotation.
Not reportedComparator
Verbatim
e6“P additions increased yields of all crops”
Claim · model-written summary
Phosphorus added on the barley crop was still available to potatoes 5 years later.
- Taxon
- potatoesSolanum tuberosume7
- Outcome
- Phosphoruse7
- Qualifier
- 5 years after it had been added on the barley crope7
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e7“Phosphorus was available to potatoes 5 years after it had been added on the barley crop”
Claim · model-written summary
Yields of barley and corn tended to be higher in the legume rotation than in the nonlegume rotation, regardless of fertilizer treatment.
- Taxon
- barley and cornHordeum vulgareZea mays subsp. mayse1
- Treatment
- legume rotatione1
- Outcome
- Yieldse1
- Direction
- highere1
- Qualifier
- regardless of the fertilizer treatmente1
- Comparator
- nonlegume rotatione1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“Yields of barley and corn tended to be higher in the legume rotation than in the nonlegume rotation, regardless of the fertilizer treatment”
Claim · model-written summary
At the highest N rate, potato yields were similar in the legume and nonlegume rotations.
- Taxon
- potatoesSolanum tuberosume1
- Treatment
- highest N fertilizer ratee1
- Outcome
- yields of potatoese1
- Direction
- no_changeinferrede1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“At the highest N fertilizer rate, yields of potatoes were similar in the two rotations”
Claim · model-written summary
Higher yields in the legume rotation resulted mainly from the available N contributed by alfalfa.
- Taxon
- alfalfa
Medicago sativae1 - Outcome
- Higher yieldse1
- Qualifier
- available N contributed by the alfalfae1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“Higher yields in the legume rotation resulted mainly from the available N contributed by the alfalfa, but other factors also appear to be involved”
Claim · model-written summary
Alfalfa grown only in the establishing year contributed available N to the succeeding corn crop in an amount comparable to alfalfa grown for longer.
- Taxon
- alfalfaMedicago sativae1
- Treatment
- Alfalfa, grown only in the establishing yeare1
- Outcome
- available Ne1
- Direction
- no_changeinferrede1
- Comparator
- alfalfa grown for a longer timee1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“Alfalfa, grown only in the establishing year, contributed available N to the succeeding corn crop in an amount comparable to alfalfa grown for a longer time”
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