Abstract
Abstract Two cultivars of lettuce plants (Lactuca sativa L. cvs Berlo and Kirsten) were grown for two months in late fall in NFT under three different nitrogen (N)‐regimes but with the same total N concentration (13.4 mM). A reference treatment with a nutrient solution containing 94% nitrate (NO3) and 6% ammonium (NH4) was compared with urea and proteinate treatments in which 20% of the NO3 of the reference treatment was replaced by either of these two N sources. Proteinate is a fertilizer produced in Turkey containing 8% amino acid N and 8% NO3‐N. For both cultivars the fresh weights of the harvested plants were unaffected by the N source as was also the total N uptake. Nitrate content, however, was considerably lower in the urea and proteinate plants, values for the three treatments ranging from 3314 to 4579 mg NO3/kg fresh wt making up from between 44.3% to 55.4% of the total plant N. Of the two cultivars, Berlo accumulated greater concentrations of NO3 than did Kirsten. The accumulation of chloride (Cl) was in the reverse order of that of NO3 with greatest concentrations occurring in the proteinate plants.
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Claims 10
Claim · model-written summary
Urea replacement did not affect harvested lettuce fresh weight relative to the reference nitrogen solution.
- Taxon
- lettuce plants
Lactuca sativae2 - Material
- Berlo and Kirstene2
- Treatment
- ureae1
- Outcome
- fresh weights of the harvested plantse0
- Direction
- unaffectede0
- Comparator
- A reference treatmente1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“For both cultivars the fresh weights of the harvested plants were unaffected by the N source as was also the total N uptake.”
e1“A reference treatment with a nutrient solution containing 94% nitrate (NO3) and 6% ammonium (NH4) was compared with urea and proteinate treatments in which 20% of the NO3 of the reference treatment was replaced by either of these two N sources.”
e2“Two cultivars of lettuce plants (Lactuca sativa L. cvs Berlo and Kirsten)”
Claim · model-written summary
Proteinate replacement did not affect harvested lettuce fresh weight relative to the reference nitrogen solution.
- Taxon
- lettuce plantsLactuca sativae2
- Material
- Berlo and Kirstene2
- Treatment
- proteinatee1
- Outcome
- fresh weights of the harvested plantse0
- Direction
- unaffectede0
- Comparator
- A reference treatmente1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“For both cultivars the fresh weights of the harvested plants were unaffected by the N source as was also the total N uptake.”
e1“A reference treatment with a nutrient solution containing 94% nitrate (NO3) and 6% ammonium (NH4) was compared with urea and proteinate treatments in which 20% of the NO3 of the reference treatment was replaced by either of these two N sources.”
e2“Two cultivars of lettuce plants (Lactuca sativa L. cvs Berlo and Kirsten)”
Claim · model-written summary
Urea replacement did not affect total nitrogen uptake in either lettuce cultivar.
- Taxon
- lettuce plantsLactuca sativae2
- Material
- Berlo and Kirstene2
- Treatment
- ureae1
- Outcome
- total N uptakee0
- Direction
- unaffectede0
- Comparator
- A reference treatmente1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“For both cultivars the fresh weights of the harvested plants were unaffected by the N source as was also the total N uptake.”
e1“A reference treatment with a nutrient solution containing 94% nitrate (NO3) and 6% ammonium (NH4) was compared with urea and proteinate treatments in which 20% of the NO3 of the reference treatment was replaced by either of these two N sources.”
e2“Two cultivars of lettuce plants (Lactuca sativa L. cvs Berlo and Kirsten)”
Claim · model-written summary
Proteinate replacement did not affect total nitrogen uptake in either lettuce cultivar.
- Taxon
- lettuce plantsLactuca sativae2
- Material
- Berlo and Kirstene2
- Treatment
- proteinatee1
- Outcome
- total N uptakee0
- Direction
- unaffectede0
- Comparator
- A reference treatmente1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“For both cultivars the fresh weights of the harvested plants were unaffected by the N source as was also the total N uptake.”
e1“A reference treatment with a nutrient solution containing 94% nitrate (NO3) and 6% ammonium (NH4) was compared with urea and proteinate treatments in which 20% of the NO3 of the reference treatment was replaced by either of these two N sources.”
e2“Two cultivars of lettuce plants (Lactuca sativa L. cvs Berlo and Kirsten)”
Claim · model-written summary
Urea replacement considerably lowered lettuce nitrate content relative to the reference solution.
- Taxon
- lettuce plantsLactuca sativae2
- Material
- Berlo and Kirstene2
- Treatment
- ureae0
- Outcome
- Nitrate contente0
- Direction
- lowere0
- Comparator
- A reference treatmente1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Nitrate content, however, was considerably lower in the urea and proteinate plants, values for the three treatments ranging from 3314 to 4579 mg NO3/kg fresh wt making up from between 44.3% to 55.4% of the total plant N.”
e1“A reference treatment with a nutrient solution containing 94% nitrate (NO3) and 6% ammonium (NH4) was compared with urea and proteinate treatments”
e2“Two cultivars of lettuce plants (Lactuca sativa L. cvs Berlo and Kirsten)”
Claim · model-written summary
Proteinate replacement considerably lowered lettuce nitrate content relative to the reference solution.
- Taxon
- lettuce plantsLactuca sativae2
- Material
- Berlo and Kirstene2
- Treatment
- proteinatee0
- Outcome
- Nitrate contente0
- Direction
- lowere0
- Comparator
- A reference treatmente1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Nitrate content, however, was considerably lower in the urea and proteinate plants, values for the three treatments ranging from 3314 to 4579 mg NO3/kg fresh wt making up from between 44.3% to 55.4% of the total plant N.”
e1“A reference treatment with a nutrient solution containing 94% nitrate (NO3) and 6% ammonium (NH4) was compared with urea and proteinate treatments”
e2“Two cultivars of lettuce plants (Lactuca sativa L. cvs Berlo and Kirsten)”
Claim · model-written summary
Lettuce nitrate content across the three nitrogen treatments ranged from 3314 to 4579 mg NO3/kg fresh wt.
- Taxon
- lettuce plantsLactuca sativae1
- Outcome
- Nitrate contente0
- Value
- 3314 to 4579 mg NO3/kg fresh wte0
- Qualifier
- the three treatmentse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Nitrate content, however, was considerably lower in the urea and proteinate plants, values for the three treatments ranging from 3314 to 4579 mg NO3/kg fresh wt making up from between 44.3% to 55.4% of the total plant N.”
e1“Two cultivars of lettuce plants (Lactuca sativa L. cvs Berlo and Kirsten)”
Claim · model-written summary
Nitrate made up between 44.3% and 55.4% of total plant nitrogen across the three treatments.
- Taxon
- lettuce plantsLactuca sativae1
- Outcome
- total plant Ne0
- Value
- 44.3% to 55.4%e0
- Qualifier
- the three treatmentse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Nitrate content, however, was considerably lower in the urea and proteinate plants, values for the three treatments ranging from 3314 to 4579 mg NO3/kg fresh wt making up from between 44.3% to 55.4% of the total plant N.”
e1“Two cultivars of lettuce plants (Lactuca sativa L. cvs Berlo and Kirsten)”
Claim · model-written summary
Berlo accumulated more nitrate than Kirsten.
- Taxon
- lettuce plantsLactuca sativae1
- Material
- Berloe0
- Outcome
- concentrations of NO3e0
- Direction
- greatere0
- Comparator
- Kirstene0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Of the two cultivars, Berlo accumulated greater concentrations of NO3 than did Kirsten.”
e1“Two cultivars of lettuce plants (Lactuca sativa L. cvs Berlo and Kirsten)”
Claim · model-written summary
Proteinate treated lettuce had the greatest chloride concentrations.
- Taxon
- lettuce plantsLactuca sativae1
- Treatment
- proteinatee0
- Compound
- chloride (Cl)e0
- Outcome
- concentrationse0
- Direction
- greateste0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The accumulation of chloride (Cl) was in the reverse order of that of NO3 with greatest concentrations occurring in the proteinate plants.”
e1“Two cultivars of lettuce plants (Lactuca sativa L. cvs Berlo and Kirsten)”
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