Abstract
Abstract Nitrogen fertilizer was applied at 0, 30,60 and 90 kg N ha ‐1 in March 1976, 1977 and 1978 to plots containing perennial ryegrass cv. Barlenna sown either alone or with white clover cv. Blanca, Sabeda, Olwen and S100 in four replicated blocks. Dry matter (DM) yield of all swards responded positively to N with the response being highest in the no‐clover swards in two of the three years. Annual DM yields were lower in the no‐clover than in the mixed swards at any given N level. The higher levels of N reduced DM yield in mixed swards at some harvests in midsummer. Swards of S100 were consistently among the lower yielding mixed swards, whereas the other three clover cultivars varied in their relative yields. There were no N x cultivar interactions for white clover yields; irrespective of cultivar, N application reduced annual white clover yield by similar amounts. It is concluded that it is beneficial to apply moderate amounts of N fertilizer to mixed swards in spring and that under these conditions the yield differences between swards including medium‐large and smaller leaved white clover cultivars are similar to differences between the inherent yield potential of these cultivars in mixed swards receiving no N.
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Claims 10
Claim · model-written summary
Dry matter yield of all swards responded positively to nitrogen fertilizer.
- Taxon
- perennial ryegrass
Lolium perennee1 - Material
- cv. Barlennae1
- Treatment
- Nitrogen fertilizere2
- Outcome
- Dry matter (DM) yielde3
- Direction
- responded positivelye3
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“perennial ryegrass cv. Barlenna sown either alone or with white clover cv. Blanca, Sabeda, Olwen and S100”
e2“Nitrogen fertilizer was applied at 0, 30,60 and 90 kg N ha”
e3“Dry matter (DM) yield of all swards responded positively to N”
Claim · model-written summary
The dry matter response to nitrogen fertilizer was highest in the no-clover swards in two of the three years.
- Taxon
- perennial ryegrassLolium perennee1
- Treatment
- Nitrogen fertilizere2
- Outcome
- responsee4
- Direction
- higheste4
- Qualifier
- no-clover swards in two of the three yearse4
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“perennial ryegrass cv. Barlenna sown either alone or with white clover cv. Blanca, Sabeda, Olwen and S100”
e2“Nitrogen fertilizer was applied at 0, 30,60 and 90 kg N ha”
e4“with the response being highest in the no-clover swards in two of the three years”
Claim · model-written summary
Annual dry matter yields were lower in no-clover swards than in mixed swards at any given nitrogen level.
- Taxon
- perennial ryegrassLolium perennee1
- Outcome
- Annual DM yieldse5
- Direction
- lowere5
- Qualifier
- at any given N levele6
- Comparator
- mixed swardse6
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“perennial ryegrass cv. Barlenna sown either alone or with white clover cv. Blanca, Sabeda, Olwen and S100”
e5“Annual DM yields were lower”
e6“than in the mixed swards at any given N level”
Claim · model-written summary
High levels of nitrogen reduced dry matter yield in mixed swards at some harvests in midsummer.
- Taxon
- perennial ryegrassLolium perennee1
- Treatment
- higher levels of Ne7
- Outcome
- DM yielde7
- Direction
- reducede7
- Qualifier
- in mixed swards at some harvests in midsummere7
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“perennial ryegrass cv. Barlenna sown either alone or with white clover cv. Blanca, Sabeda, Olwen and S100”
e7“The higher levels of N reduced DM yield in mixed swards at some harvests in midsummer”
Claim · model-written summary
Swards with white clover cultivar S100 were consistently among the lower yielding mixed swards.
- Taxon
- white clover
Trifolium repense1 - Material
- S100e2
- Outcome
- yielde2
- Direction
- lower yieldinge2
- Qualifier
- consistentlye2
- Comparator
- mixed swardse2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“perennial ryegrass cv. Barlenna sown either alone or with white clover cv. Blanca, Sabeda, Olwen and S100”
e2“Swards of S100 were consistently among the lower yielding mixed swards”
Claim · model-written summary
The other three white clover cultivars varied in their relative yields.
- Taxon
- white cloverTrifolium repense1
- Material
- Blanca, Sabeda, Olwene1
- Outcome
- relative yieldse2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“perennial ryegrass cv. Barlenna sown either alone or with white clover cv. Blanca, Sabeda, Olwen and S100”
e2“the other three clover cultivars varied in their relative yields”
Claim · model-written summary
Nitrogen application reduced annual white clover yield by similar amounts irrespective of cultivar.
- Taxon
- white cloverTrifolium repense1
- Treatment
- N applicatione2
- Outcome
- annual white clover yielde2
- Direction
- reducede2
- Qualifier
- by similar amountse2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“perennial ryegrass cv. Barlenna sown either alone or with white clover cv. Blanca, Sabeda, Olwen and S100”
e2“irrespective of cultivar, N application reduced annual white clover yield by similar amounts”
Claim · model-written summary
There were no nitrogen by cultivar interactions for white clover yields.
- Taxon
- white cloverTrifolium repense1
- Outcome
- N x cultivar interactions for white clover yieldse2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“perennial ryegrass cv. Barlenna sown either alone or with white clover cv. Blanca, Sabeda, Olwen and S100”
e2“There were no N x cultivar interactions for white clover yields”
Claim · model-written summary
It is beneficial to apply moderate amounts of nitrogen fertilizer to mixed swards in spring.
- Taxon
- perennial ryegrassLolium perennee1
- Outcome
- apply moderate amounts of N fertilizer to mixed swards in springe2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“perennial ryegrass cv. Barlenna sown either alone or with white clover cv. Blanca, Sabeda, Olwen and S100”
e2“it is beneficial to apply moderate amounts of N fertilizer to mixed swards in spring”
Claim · model-written summary
Under these conditions, yield differences between swards are similar to differences between the inherent yield potential of white clover cultivars in mixed swards receiving no nitrogen.
- Taxon
- white cloverTrifolium repense1
- Outcome
- yield differencese3
- Direction
- no_changeinferrede2
- Comparator
- differences between the inherent yield potential of these cultivars in mixed swards receiving no Ne2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“perennial ryegrass cv. Barlenna sown either alone or with white clover cv. Blanca, Sabeda, Olwen and S100”
e2“are similar to differences between the inherent yield potential of these cultivars in mixed swards receiving no N”
e3“the yield differences between swards”
The same questions in other papers
nitrogen · yield · Trifolium repens (white clover)Results differ
12 papers in the same direction as this paper · 11 in the opposite direction
- positive
- no effect
- no effect
20 papers more in this group
See all 24 papers →fertilization · growth · Lolium perenne (perennial ryegrass)Positive and negative results
27 papers in the same direction as this paper · 5 in the opposite direction · 2 reporting no difference from an alternative
- positive
- negative
- negative
31 papers more in this group
See all 35 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.