Abstract
Abstract Two experiments of 4 year duration were conducted on organic soil sites which had accumulated P and K from several years of previous fertilization. There were no adverse consequences to an onion crop (Allium cepaL.) when P and K were omitted from the fertilizer program until the third year in one experiment. In the other there was no response to P and K even after 4 years of omission. Soil test levels declined substantially when P and K were not applied and also, although to a lesser degree, when they were applied at 112 and 168 kg/ha as P2O5and K2O respectively In contrast there were yield responses to N in most years. Nitrogen stimulated early development and always accelerated maturity as measured by the percentage of onion tops down in middle or later August. Concentrations of N, P and K in leaves or immature bulbs at midseason were always higher when these nutrients were applied indicating increased uptake even though yield responses did not always occur. When soil tests are relatively high, there appears to be little risk in reducing P and K providing the resulting decline in soil tests are monitored yearly. Eliminating N, however, could be very risky for early planted onions, even though substantial quantities can be released from organic soils later in the season.
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Claims 12
Claim · model-written summary
Omitting phosphorus and potassium did not harm onion crops until the third year in one experiment.
- Taxon
- onion crop (Allium cepaL.)
Allium cepae0 - Treatment
- P and K were omittede0
- Outcome
- adverse consequencese0
- Direction
- no adverse consequencese0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“There were no adverse consequences to an onion crop (Allium cepaL.) when P and K were omitted from the fertilizer program until the third year in one experiment.”
Claim · model-written summary
Another onion experiment showed no response to phosphorus and potassium after four years of omission.
- Taxon
- onion crop (Allium cepaL.)Allium cepae1
- Treatment
- P and Ke0
- Outcome
- responsee0
- Direction
- no responsee0
- Qualifier
- 4 years of omissione0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“In the other there was no response to P and K even after 4 years of omission.”
e1“onion crop (Allium cepaL.)”
Claim · model-written summary
Soil test levels declined substantially without P and K fertilization in onion plots.
- Taxon
- onion crop (Allium cepaL.)Allium cepae1
- Treatment
- P and K were not appliede0
- Outcome
- Soil test levelse0
- Direction
- declined substantiallye0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Soil test levels declined substantially when P and K were not applied and also, although to a lesser degree, when they were applied at 112 and 168 kg/ha as P2O5and K2O respectively”
e1“onion crop (Allium cepaL.)”
Claim · model-written summary
Soil test levels also declined at the stated P and K fertilizer rates, to a lesser degree.
- Taxon
- onion crop (Allium cepaL.)Allium cepae1
- Treatment
- 112 and 168 kg/ha as P2O5and K2Oe0
- Outcome
- Soil test levelse0
- Direction
- declinede0
- Qualifier
- to a lesser degreee0
- Comparator
- P and K were not appliede0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Soil test levels declined substantially when P and K were not applied and also, although to a lesser degree, when they were applied at 112 and 168 kg/ha as P2O5and K2O respectively”
e1“onion crop (Allium cepaL.)”
Claim · model-written summary
Nitrogen increased onion yield in most years.
- Taxon
- onion crop (Allium cepaL.)Allium cepae1
- Treatment
- Ne0
- Outcome
- yield responsese0
Not reportedComparatorDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“In contrast there were yield responses to N in most years.”
e1“onion crop (Allium cepaL.)”
Claim · model-written summary
Nitrogen stimulated early onion development.
- Taxon
- onion crop (Allium cepaL.)Allium cepae1
- Treatment
- Nitrogene0
- Outcome
- early developmente0
- Direction
- stimulatede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Nitrogen stimulated early development and always accelerated maturity as measured by the percentage of onion tops down in middle or later August.”
e1“onion crop (Allium cepaL.)”
Claim · model-written summary
Nitrogen accelerated onion maturity in every year.
- Taxon
- onion crop (Allium cepaL.)Allium cepae1
- Treatment
- Nitrogene0
- Outcome
- maturitye0
- Direction
- acceleratede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Nitrogen stimulated early development and always accelerated maturity as measured by the percentage of onion tops down in middle or later August.”
e1“onion crop (Allium cepaL.)”
Claim · model-written summary
Applying N raised its concentration in onion leaves or immature bulbs at midseason.
- Taxon
- onion crop (Allium cepaL.)Allium cepae1
- Organ / stage
- leaves or immature bulbse0
- Treatment
- these nutrientse0
- Outcome
- Ne0
- Direction
- highere0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Concentrations of N, P and K in leaves or immature bulbs at midseason were always higher when these nutrients were applied indicating increased uptake even though yield responses did not always occur.”
e1“onion crop (Allium cepaL.)”
Claim · model-written summary
Applying P raised its concentration in onion leaves or immature bulbs at midseason.
- Taxon
- onion crop (Allium cepaL.)Allium cepae1
- Organ / stage
- leaves or immature bulbse0
- Treatment
- these nutrientse0
- Outcome
- Pe0
- Direction
- highere0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Concentrations of N, P and K in leaves or immature bulbs at midseason were always higher when these nutrients were applied indicating increased uptake even though yield responses did not always occur.”
e1“onion crop (Allium cepaL.)”
Claim · model-written summary
Applying K raised its concentration in onion leaves or immature bulbs at midseason.
- Taxon
- onion crop (Allium cepaL.)Allium cepae1
- Organ / stage
- leaves or immature bulbse0
- Treatment
- these nutrientse0
- Outcome
- Ke0
- Direction
- highere0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Concentrations of N, P and K in leaves or immature bulbs at midseason were always higher when these nutrients were applied indicating increased uptake even though yield responses did not always occur.”
e1“onion crop (Allium cepaL.)”
Claim · model-written summary
Reduced P and K fertilizer may be low risk on high-testing onion soil if soil tests are monitored annually.
- Taxon
- onion crop (Allium cepaL.)Allium cepae1
- Outcome
- reducing P and Ke0
- Qualifier
- soil tests are monitored yearlye0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“When soil tests are relatively high, there appears to be little risk in reducing P and K providing the resulting decline in soil tests are monitored yearly.”
e1“onion crop (Allium cepaL.)”
Claim · model-written summary
Eliminating nitrogen may be risky for early planted onions.
- Taxon
- onion crop (Allium cepaL.)Allium cepae1
- Outcome
- Eliminating Ne0
- Qualifier
- early planted onionse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Eliminating N, however, could be very risky for early planted onions”
e1“onion crop (Allium cepaL.)”
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- no effect
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See all 184 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.