Abstract
Abstract Nutrient concentrations in plant tissues were related to yield responses in three fertiliser experiments on virgin Addison sandy loam. Yield responses indicated initial requirements for vigorous growth of white clover of at least 30 cwt agricultural limestone per acre, phosphate equivalent to 9 to 12 cwt superphosphate, 3 to 4 cwt potassium chloride, about 20 lb elemental sulphur, 5 lb each of copper and zinc sulphates, and 1 oz sodium molybdate. Indicated maintenance needs were about 5 cwt limestone per acre per annum, 6 cwt superphosphate, 3 to 4 cwt potassium chloride, and 20 lb elemental sulphur. The low retentive capacity of this soil for phosphate, sulphate, potassium, and calcium, combined with a mean annual rainfall of about 100 in., led to rapid leaching losses of nutrients and therefore abnormally high maintenance needs. Associated with yield responses, N concentrations in white clover leaves (blades plus petiole) increased with increasing rates of mono‐calcium phosphate, lime, sulphur, or sulphate, and with molybdenum applications. Because of variation between cuts in the N status of clovers, ratios of nutrients to N were examined. In these circumstances ratios appeared to be superior to absolute concentrations for diagnosis of nutrient status. Yield response to P occurred when N∶P ratios in white clover leaves were above about 14∶1. N:S ratios in clover leaves above about 18∶1 indicated S deficiency. Yield responses to copper of more than 100 percent were associated with mean Cu concentrations in leaves of copper‐deficient white clover plants of 2.0 ppm and N∶Cu ratios above 11,000:1. Slightly higher Cu levels were found in some of the most stunted copper‐deficient plants. Yield responses to zinc averaging 32 percent were associated with a mean concentration in leaves of zinc‐deficient white clover plants of 15 ppm, P∶Zn ratios above 200∶1, and N:Zn ratios above 2,200∶1.
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Claims 18
Claim · model-written summary
Yield responses indicated initial limestone requirement of at least 30 cwt per acre.
- Taxon
- white clover
Trifolium repense0 - Treatment
- agricultural limestonee0
- Outcome
- initial requirements for vigorous growthe0
- Value
- at least 30 cwt agricultural limestone per acree0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Yield responses indicated initial requirements for vigorous growth of white clover of at least 30 cwt agricultural limestone per acre, phosphate equivalent to 9 to 12 cwt superphosphate, 3 to 4 cwt potassium chloride, about 20 lb elemental sulphur, 5 lb each of copper and zinc sulphates, and 1 oz sodium molybdate.”
Claim · model-written summary
Initial phosphate requirement was equivalent to 9 to 12 cwt superphosphate.
- Taxon
- white cloverTrifolium repense0
- Treatment
- phosphatee0
- Outcome
- initial requirements for vigorous growthe0
- Value
- 9 to 12 cwt superphosphatee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Yield responses indicated initial requirements for vigorous growth of white clover of at least 30 cwt agricultural limestone per acre, phosphate equivalent to 9 to 12 cwt superphosphate, 3 to 4 cwt potassium chloride, about 20 lb elemental sulphur, 5 lb each of copper and zinc sulphates, and 1 oz sodium molybdate.”
Claim · model-written summary
Initial potassium chloride requirement was 3 to 4 cwt.
- Taxon
- white cloverTrifolium repense0
- Treatment
- potassium chloridee0
- Outcome
- initial requirements for vigorous growthe0
- Value
- 3 to 4 cwt potassium chloridee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Yield responses indicated initial requirements for vigorous growth of white clover of at least 30 cwt agricultural limestone per acre, phosphate equivalent to 9 to 12 cwt superphosphate, 3 to 4 cwt potassium chloride, about 20 lb elemental sulphur, 5 lb each of copper and zinc sulphates, and 1 oz sodium molybdate.”
Claim · model-written summary
Initial elemental sulphur requirement was about 20 lb.
- Taxon
- white cloverTrifolium repense0
- Treatment
- elemental sulphure0
- Outcome
- initial requirements for vigorous growthe0
- Value
- about 20 lb elemental sulphure0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Yield responses indicated initial requirements for vigorous growth of white clover of at least 30 cwt agricultural limestone per acre, phosphate equivalent to 9 to 12 cwt superphosphate, 3 to 4 cwt potassium chloride, about 20 lb elemental sulphur, 5 lb each of copper and zinc sulphates, and 1 oz sodium molybdate.”
Claim · model-written summary
Initial copper and zinc sulphate requirements were 5 lb each.
- Taxon
- white cloverTrifolium repense0
- Treatment
- copper and zinc sulphatese0
- Outcome
- initial requirements for vigorous growthe0
- Value
- 5 lb eache0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Yield responses indicated initial requirements for vigorous growth of white clover of at least 30 cwt agricultural limestone per acre, phosphate equivalent to 9 to 12 cwt superphosphate, 3 to 4 cwt potassium chloride, about 20 lb elemental sulphur, 5 lb each of copper and zinc sulphates, and 1 oz sodium molybdate.”
Claim · model-written summary
Initial sodium molybdate requirement was 1 oz.
- Taxon
- white cloverTrifolium repense0
- Treatment
- sodium molybdatee0
- Outcome
- initial requirements for vigorous growthe0
- Value
- 1 oz sodium molybdatee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Yield responses indicated initial requirements for vigorous growth of white clover of at least 30 cwt agricultural limestone per acre, phosphate equivalent to 9 to 12 cwt superphosphate, 3 to 4 cwt potassium chloride, about 20 lb elemental sulphur, 5 lb each of copper and zinc sulphates, and 1 oz sodium molybdate.”
Claim · model-written summary
Maintenance limestone need was about 5 cwt per acre annually.
- Taxon
- white cloverTrifolium repenst0
- Treatment
- limestonee0
- Outcome
- maintenance needse0
- Value
- about 5 cwt limestone per acre per annume0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Indicated maintenance needs were about 5 cwt limestone per acre per annum, 6 cwt superphosphate, 3 to 4 cwt potassium chloride, and 20 lb elemental sulphur.”
t0“white clover”
Claim · model-written summary
Maintenance superphosphate need was 6 cwt.
- Taxon
- white cloverTrifolium repenst0
- Treatment
- superphosphatee0
- Outcome
- maintenance needse0
- Value
- 6 cwt superphosphatee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Indicated maintenance needs were about 5 cwt limestone per acre per annum, 6 cwt superphosphate, 3 to 4 cwt potassium chloride, and 20 lb elemental sulphur.”
t0“white clover”
Claim · model-written summary
Maintenance potassium chloride need was 3 to 4 cwt.
- Taxon
- white cloverTrifolium repenst0
- Treatment
- potassium chloridee0
- Outcome
- maintenance needse0
- Value
- 3 to 4 cwt potassium chloridee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Indicated maintenance needs were about 5 cwt limestone per acre per annum, 6 cwt superphosphate, 3 to 4 cwt potassium chloride, and 20 lb elemental sulphur.”
t0“white clover”
Claim · model-written summary
Maintenance elemental sulphur need was 20 lb.
- Taxon
- white cloverTrifolium repenst0
- Treatment
- elemental sulphure0
- Outcome
- maintenance needse0
- Value
- 20 lb elemental sulphure0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Indicated maintenance needs were about 5 cwt limestone per acre per annum, 6 cwt superphosphate, 3 to 4 cwt potassium chloride, and 20 lb elemental sulphur.”
t0“white clover”
Claim · model-written summary
Soil leaching contributed to unusually high maintenance needs.
- Taxon
- white cloverTrifolium repenst0
- Outcome
- abnormally high maintenance needse0
- Qualifier
- rapid leaching losses of nutrientse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The low retentive capacity of this soil for phosphate, sulphate, potassium, and calcium, combined with a mean annual rainfall of about 100 in., led to rapid leaching losses of nutrients and therefore abnormally high maintenance needs.”
t0“white clover”
Claim · model-written summary
Leaf nitrogen concentration increased with mono-calcium phosphate, lime, sulphur, sulphate or molybdenum application.
- Taxon
- white cloverTrifolium repense0
- Treatment
- mono‐calcium phosphate, lime, sulphur, or sulphate, and with molybdenum applicationse0
- Outcome
- N concentrations in white clover leavese0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Associated with yield responses, N concentrations in white clover leaves (blades plus petiole) increased with increasing rates of mono‐calcium phosphate, lime, sulphur, or sulphate, and with molybdenum applications.”
Claim · model-written summary
Nutrient to nitrogen ratios appeared better than absolute concentrations for nutrient diagnosis.
- Taxon
- white cloverTrifolium repenst0
- Outcome
- diagnosis of nutrient statuse0
- Direction
- superiore0
- Comparator
- absolute concentrationse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“In these circumstances ratios appeared to be superior to absolute concentrations for diagnosis of nutrient status.”
t0“white clover”
Claim · model-written summary
Yield responded to phosphorus above a leaf N:P ratio of about 14:1.
- Taxon
- white cloverTrifolium repense0
- Organ / stage
- leavese0
- Outcome
- Yield response to Pe0
- Direction
- responsee0
- Value
- above about 14∶1e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Yield response to P occurred when N∶P ratios in white clover leaves were above about 14∶1.”
Claim · model-written summary
Leaf N:S ratios above about 18:1 indicated sulphur deficiency.
TrifoliumNot reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“N:S ratios in clover leaves above about 18∶1 indicated S deficiency.”
Claim · model-written summary
Copper treatment gave over 100 percent yield responses with copper-deficient leaf concentrations averaging 2.0 ppm and N:Cu ratios above 11,000:1.
- Taxon
- white cloverTrifolium repense0
- Organ / stage
- leavese0
- Outcome
- Yield responses to coppere0
- Value
- more than 100 percente0
- Qualifier
- mean Cu concentrations in leaves of copper‐deficient white clover plants of 2.0 ppm and N∶Cu ratios above 11,000:1e0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Yield responses to copper of more than 100 percent were associated with mean Cu concentrations in leaves of copper‐deficient white clover plants of 2.0 ppm and N∶Cu ratios above 11,000:1.”
Claim · model-written summary
Some of the most stunted copper-deficient plants had slightly higher copper levels.
- Taxon
- white cloverTrifolium repenst0
- Outcome
- Cu levelse0
- Direction
- Slightly highere0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Slightly higher Cu levels were found in some of the most stunted copper‐deficient plants.”
t0“white clover”
Claim · model-written summary
Zinc treatment gave 32 percent average yield responses associated with leaf zinc at 15 ppm and elevated P:Zn and N:Zn ratios.
- Taxon
- white cloverTrifolium repense0
- Organ / stage
- leavese0
- Outcome
- Yield responses to zince0
- Value
- 32 percente0
- Qualifier
- mean concentration in leaves of zinc‐deficient white clover plants of 15 ppm, P∶Zn ratios above 200∶1, and N:Zn ratios above 2,200∶1e0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Yield responses to zinc averaging 32 percent were associated with a mean concentration in leaves of zinc‐deficient white clover plants of 15 ppm, P∶Zn ratios above 200∶1, and N:Zn ratios above 2,200∶1.”
The same questions in other papers
sulfur atom · nutrient: content · Trifolium repens (white clover)Results agree
1 paper in the same direction as this paper
- positive
sulfate · nutrient: content · Trifolium repens (white clover)Results agree
3 papers in the same direction as this paper
- positive
- positive
- positive
molybdenum atom · nutrient: content · Trifolium repens (white clover)Results agree
4 papers in the same direction as this paper
- positive
- positive
- positive
1 paper more in this group
See all 5 papers →lime · nutrient: content · Trifolium repens (white clover)Positive and negative results
9 papers in the same direction as this paper · 1 in the opposite direction
- no effect
- positive
- positive
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See all 11 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.