Abstract
The application of 50 kg N/ha in March as urea or calcium ammonium nitrate for early season herbage production was studied for its effects on white clover productivity in terms of clover dry matter production and nitrogen fixation capacity. Average clover content in the sward throughout the year was 15.4 and 15.1% for the urea and calcium ammonium nitrate treatments, respectively, compared with 21.3% for the zero N (control) treatment. Total clover production was 1.52 t/ha for the urea and 1.51 for calcium ammonium nitrate treatments compared with 2.00 t/ha for the control. The control plots fixed 194 kg N/ha/an, the corresponding figures for urea and calcium ammonium nitrate treatments being 165 kg and 142 kg, respectively. Although urea and calcium ammonium nitrate reduced the clover content of the sward to a similar degree, urea appeared to have a less damaging effect on the symbiotic system. Results show that when N fertiliser is applied to mixed swards, the clover component utilises soil N along with atmospheric N2. However, accumulation of nitrate in the legume following application of N is considerably less than that observed in grass. The effects of grazing and the return of N in animal excreta on clover N2 fixation were studied in a system which allowed grazing of the sward but prevented animal ingress on the protected sward area. N fixation rates in the enclosed areas were 12% lower than values observed in plots to which animals had free access, although this difference was not statistically significant at the 5% level. Restricted plots were more selectively and intensively grazed and this had a more harmful effect on N2 fixation than the return of N via the grazing animal.
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Claims 11
Claim · model-written summary
Urea reduced average white clover content to 15.4% compared with 21.3% in the zero-N control.
- Taxon
- White Clover
Trifolium repenst0 - Treatment
- application of 50 kg N/ha in March as ureae0
- Outcome
- clover contente1
- Direction
- reducede4
- Value
- 15.4e1
- Comparator
- zero N (control) treatmente1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“on White Clover (Trifolium repens) Performance”
e0“The application of 50 kg N/ha in March as urea or calcium ammonium nitrate”
e1“Average clover content in the sward throughout the year was 15.4 and 15.1% for the urea and calcium ammonium nitrate treatments, respectively, compared with 21.3% for the zero N (control) treatment”
e4“Although urea and calcium ammonium nitrate reduced the clover content of the sward to a similar degree, urea appeared to have a less damaging effect on the symbiotic system”
Claim · model-written summary
Calcium ammonium nitrate reduced average white clover content to 15.1% compared with 21.3% in the zero-N control.
- Taxon
- White CloverTrifolium repenst0
- Treatment
- calcium ammonium nitratee0
- Outcome
- clover contente1
- Direction
- reducede4
- Value
- 15.1%e1
- Comparator
- zero N (control) treatmente1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“on White Clover (Trifolium repens) Performance”
e0“The application of 50 kg N/ha in March as urea or calcium ammonium nitrate”
e1“Average clover content in the sward throughout the year was 15.4 and 15.1% for the urea and calcium ammonium nitrate treatments, respectively, compared with 21.3% for the zero N (control) treatment”
e4“Although urea and calcium ammonium nitrate reduced the clover content of the sward to a similar degree, urea appeared to have a less damaging effect on the symbiotic system”
Claim · model-written summary
Urea reduced total clover production to 1.52 t/ha compared with 2.00 t/ha in the control.
- Taxon
- White CloverTrifolium repenst0
- Treatment
- ureae2
- Outcome
- Total clover productione2
- Direction
- lowerinferrede2
- Value
- 1.52 t/hae2
- Comparator
- the controle2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“on White Clover (Trifolium repens) Performance”
e2“Total clover production was 1.52 t/ha for the urea and 1.51 for calcium ammonium nitrate treatments compared with 2.00 t/ha for the control”
Claim · model-written summary
Calcium ammonium nitrate reduced total clover production to 1.51 compared with 2.00 t/ha in the control.
- Taxon
- White CloverTrifolium repenst0
- Treatment
- calcium ammonium nitrate treatmentse2
- Outcome
- Total clover productione2
- Direction
- lowerinferrede2
- Value
- 1.51e2
- Comparator
- the controle2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“on White Clover (Trifolium repens) Performance”
e2“Total clover production was 1.52 t/ha for the urea and 1.51 for calcium ammonium nitrate treatments compared with 2.00 t/ha for the control”
Claim · model-written summary
Urea-treated plots fixed 165 kg N/ha/an compared with 194 kg N/ha/an in control plots.
- Taxon
- White CloverTrifolium repenst0
- Treatment
- ureae3
- Outcome
- fixede3
- Direction
- lowerinferrede3
- Value
- 165 kge3
- Comparator
- control plotse3
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“on White Clover (Trifolium repens) Performance”
e3“The control plots fixed 194 kg N/ha/an, the corresponding figures for urea and calcium ammonium nitrate treatments being 165 kg and 142 kg, respectively”
Claim · model-written summary
Calcium ammonium nitrate-treated plots fixed 142 kg N/ha/an compared with 194 kg N/ha/an in control plots.
- Taxon
- White CloverTrifolium repenst0
- Treatment
- calcium ammonium nitrate treatmentse3
- Outcome
- fixede3
- Direction
- lowerinferrede3
- Value
- 142 kge3
- Comparator
- control plotse3
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“on White Clover (Trifolium repens) Performance”
e3“The control plots fixed 194 kg N/ha/an, the corresponding figures for urea and calcium ammonium nitrate treatments being 165 kg and 142 kg, respectively”
Claim · model-written summary
Urea appeared to have a less damaging effect on the symbiotic system than calcium ammonium nitrate.
- Taxon
- White CloverTrifolium repenst0
- Treatment
- ureae4
- Outcome
- symbiotic systeme4
- Direction
- less damaginge4
- Comparator
- calcium ammonium nitratee4
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“on White Clover (Trifolium repens) Performance”
e4“Although urea and calcium ammonium nitrate reduced the clover content of the sward to a similar degree, urea appeared to have a less damaging effect on the symbiotic system”
Claim · model-written summary
Nitrate accumulation in the legume after N application is considerably less than in grass.
Verbatim
e5“accumulation of nitrate in the legume following application of N is considerably less than that observed in grass”
Claim · model-written summary
When N fertiliser is applied to mixed swards, the clover component uses soil N along with atmospheric N2.
Verbatim
e6“Results show that when N fertiliser is applied to mixed swards, the clover component utilises soil N along with atmospheric N2”
Claim · model-written summary
N fixation rates in enclosed areas were 12% lower than in plots with free animal access, not significant at the 5% level.
- Taxon
- White CloverTrifolium repenst0
- Treatment
- enclosed arease7
- Outcome
- N fixation ratese7
- Direction
- lowere7
- Value
- 12%e7
- Comparator
- plots to which animals had free accesse7
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“on White Clover (Trifolium repens) Performance”
e7“N fixation rates in the enclosed areas were 12% lower than values observed in plots to which animals had free access, although this difference was not statistically significant at the 5% level”
Claim · model-written summary
Restricted, more intensively grazed plots reduced N2 fixation more than the return of N via grazing animals.
- Taxon
- White CloverTrifolium repenst0
- Treatment
- more selectively and intensively grazede1
- Outcome
- N2 fixatione1
- Direction
- more harmfule1
- Comparator
- the return of N via the grazing animale1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“on White Clover (Trifolium repens) Performance”
e1“Restricted plots were more selectively and intensively grazed and this had a more harmful effect on N2 fixation than the return of N via the grazing animal”
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See all 8 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.