Abstract
BACKGROUND AND AIMS: Tea (Camellia sinensis) is considered to be acid tolerant and prefers ammonium nutrition, but the interaction between root zone acidity and N form is not properly understood. The present study was performed to characterize their interaction with respect to growth and mineral nutrition. METHODS: Tea plants were hydroponically cultured with NH4+, NO3- and NH(4+) + NO3-, at pH 4.0, 5.0 and 6.0, which were maintained by pH stat systems. KEY RESULTS: Plants supplied with NO3- showed yellowish leaves resembling nitrogen deficiency and grew much slower than those receiving NH4+ or NH(4+) + NO3- irrespective of root-zone pH. Absorption of NH4+ was 2- to 3.4-fold faster than NO3- when supplied separately, and 6- to 16-fold faster when supplied simultaneously. Nitrate-grown plants had significantly reduced glutamine synthetase activity, and lower concentrations of total N, free amino acids and glucose in the roots, but higher concentrations of cations and carboxylates (mainly oxalate) than those grown with NH4+ or NH(4+) + NO3-. Biomass production was largest at pH 5.0 regardless of N form, and was drastically reduced by a combination of high root-zone pH and NO3-. Low root-zone pH reduced root growth only in NO(3-)-fed plants. Absorption of N followed a similar pattern as root-zone pH changed, showing highest uptake rates at pH 5.0. The concentrations of total N, free amino acids, sugars and the activity of GS were generally not influenced by pH, whereas the concentrations of cations and carboxylates were generally increased with increasing root-zone pH. CONCLUSIONS: Tea plants are well-adapted to NH(4+)-rich environments by exhibiting a high capacity for NH4+ assimilation in their roots, reflected in strongly increased key enzyme activities and improved carbohydrate status. The poor plant growth with NO3- was largely associated with inefficient absorption of this N source. Decreased growth caused by inappropriate external pH corresponded well with the declining absorption of nitrogen.
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Claims 17
Claim · model-written summary
Tea plants supplied with NO3- grew much slower than those receiving NH4+ or NH4+ plus NO3-, irrespective of root-zone pH.
- Taxon
- Camellia sinensis
Camellia sinensist0 - Treatment
- NO3-e1
- Outcome
- grewe1
- Direction
- slowere1
- Comparator
- NH4+ or NH(4+) + NO3-e1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Tea ( Camellia sinensis ) Plants”
e1“Plants supplied with NO3- showed yellowish leaves resembling nitrogen deficiency and grew much slower than those receiving NH4+ or NH(4+) + NO3- irrespective of root-zone pH”
Claim · model-written summary
Absorption of NH4+ was 2- to 3.4-fold faster than NO3- when the two forms were supplied separately.
- Taxon
- Camellia sinensisCamellia sinensist0
- Treatment
- when supplied separatelye2
- Outcome
- Absorption of NH4+e2
- Direction
- fastere2
- Value
- 2- to 3.4-folde2
- Comparator
- NO3-e2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Tea ( Camellia sinensis ) Plants”
e2“Absorption of NH4+ was 2- to 3.4-fold faster than NO3- when supplied separately, and 6- to 16-fold faster when supplied simultaneously”
Claim · model-written summary
Absorption of NH4+ was 6- to 16-fold faster than NO3- when the two forms were supplied simultaneously.
- Taxon
- Camellia sinensisCamellia sinensist0
- Treatment
- when supplied simultaneouslye2
- Outcome
- Absorption of NH4+e2
- Direction
- fastere2
- Value
- 6- to 16-folde2
- Comparator
- NO3-e2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Tea ( Camellia sinensis ) Plants”
e2“Absorption of NH4+ was 2- to 3.4-fold faster than NO3- when supplied separately, and 6- to 16-fold faster when supplied simultaneously”
Claim · model-written summary
Nitrate-grown tea plants had significantly reduced glutamine synthetase activity compared with NH4+ or NH4+ plus NO3- grown plants.
- Taxon
- Camellia sinensisCamellia sinensist0
- Treatment
- Nitrate-growne4
- Gene
- glutamine synthetasee4
- Outcome
- glutamine synthetase activitye4
- Direction
- reducede4
- Comparator
- NH4+ or NH(4+) + NO3-e5
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Tea ( Camellia sinensis ) Plants”
e4“Nitrate-grown plants had significantly reduced glutamine synthetase activity”
e5“than those grown with NH4+ or NH(4+) + NO3-”
Claim · model-written summary
Nitrate-grown tea plants had lower root concentrations of total N, free amino acids and glucose than NH4+ or NH4+ plus NO3- grown plants.
- Taxon
- Camellia sinensisCamellia sinensist0
- Organ / stage
- rootse6
- Treatment
- Nitrate-growne4
- Outcome
- concentrations of total N, free amino acids and glucosee6
- Direction
- lowere6
- Comparator
- NH4+ or NH(4+) + NO3-e5
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Tea ( Camellia sinensis ) Plants”
e4“Nitrate-grown plants had significantly reduced glutamine synthetase activity”
e5“than those grown with NH4+ or NH(4+) + NO3-”
e6“and lower concentrations of total N, free amino acids and glucose in the roots”
Claim · model-written summary
Nitrate-grown tea plants had higher concentrations of cations and carboxylates, mainly oxalate, than NH4+ or NH4+ plus NO3- grown plants.
- Taxon
- Camellia sinensisCamellia sinensist0
- Treatment
- Nitrate-growne4
- Outcome
- concentrations of cations and carboxylatese7
- Direction
- highere7
- Qualifier
- mainly oxalatee7
- Comparator
- NH4+ or NH(4+) + NO3-e5
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Tea ( Camellia sinensis ) Plants”
e4“Nitrate-grown plants had significantly reduced glutamine synthetase activity”
e5“than those grown with NH4+ or NH(4+) + NO3-”
e7“but higher concentrations of cations and carboxylates (mainly oxalate)”
Claim · model-written summary
Biomass production of tea was largest at root-zone pH 5.0 regardless of N form.
- Taxon
- Camellia sinensisCamellia sinensist0
- Treatment
- root-zone pHe1
- Outcome
- Biomass productione1
- Direction
- largeste1
- Qualifier
- regardless of N forme1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Tea ( Camellia sinensis ) Plants”
e1“Biomass production was largest at pH 5.0 regardless of N form, and was drastically reduced by a combination of high root-zone pH and NO3-”
Claim · model-written summary
Biomass production of tea was drastically reduced by a combination of high root-zone pH and NO3-.
- Taxon
- Camellia sinensisCamellia sinensist0
- Treatment
- a combination of high root-zone pH and NO3-e1
- Outcome
- Biomass productione1
- Direction
- drastically reducede1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Tea ( Camellia sinensis ) Plants”
e1“Biomass production was largest at pH 5.0 regardless of N form, and was drastically reduced by a combination of high root-zone pH and NO3-”
Claim · model-written summary
Low root-zone pH reduced root growth of tea only in NO3--fed plants.
- Taxon
- Camellia sinensisCamellia sinensist0
- Treatment
- Low root-zone pHe1
- Outcome
- root growthe1
- Direction
- reducede1
- Qualifier
- only in NO(3-)-fed plantse1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Tea ( Camellia sinensis ) Plants”
e1“Low root-zone pH reduced root growth only in NO(3-)-fed plants”
Claim · model-written summary
Absorption of N followed a similar pattern as root-zone pH changed, with the highest uptake rates at pH 5.0.
- Taxon
- Camellia sinensisCamellia sinensist0
- Treatment
- root-zone pHe1
- Outcome
- Absorption of Ne1
- Direction
- higheste1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Tea ( Camellia sinensis ) Plants”
e1“Absorption of N followed a similar pattern as root-zone pH changed, showing highest uptake rates at pH 5.0”
Claim · model-written summary
Concentrations of total N, free amino acids and sugars in tea were generally not influenced by pH.
- Taxon
- Camellia sinensisCamellia sinensist0
- Treatment
- pHe1
- Outcome
- concentrations of total N, free amino acids, sugarse1
- Direction
- not influencede1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Tea ( Camellia sinensis ) Plants”
e1“The concentrations of total N, free amino acids, sugars and the activity of GS were generally not influenced by pH”
Claim · model-written summary
Glutamine synthetase activity in tea was generally not influenced by pH.
- Taxon
- Camellia sinensisCamellia sinensist0
- Treatment
- pHe1
- Gene
- GSe1
- Outcome
- the activity of GSe1
- Direction
- not influencede1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Tea ( Camellia sinensis ) Plants”
e1“The concentrations of total N, free amino acids, sugars and the activity of GS were generally not influenced by pH”
Claim · model-written summary
Concentrations of cations and carboxylates in tea generally increased with increasing root-zone pH.
- Taxon
- Camellia sinensisCamellia sinensist0
- Treatment
- increasing root-zone pHe1
- Outcome
- concentrations of cations and carboxylatese1
- Direction
- increasede1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Tea ( Camellia sinensis ) Plants”
e1“whereas the concentrations of cations and carboxylates were generally increased with increasing root-zone pH”
Claim · model-written summary
Tea in NH(4+)-rich environments shows strongly increased key enzyme activities, associated with high NH4+ assimilation capacity in the roots.
- Taxon
- Camellia sinensisCamellia sinensist0
- Treatment
- NH(4+)-rich environmentse1
- Outcome
- key enzyme activitiese1
- Direction
- strongly increasede1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Tea ( Camellia sinensis ) Plants”
e1“Tea plants are well-adapted to NH(4+)-rich environments by exhibiting a high capacity for NH4+ assimilation in their roots, reflected in strongly increased key enzyme activities and improved carbohydrate status”
Claim · model-written summary
Tea in NH(4+)-rich environments shows improved carbohydrate status.
- Taxon
- Camellia sinensisCamellia sinensist0
- Treatment
- NH(4+)-rich environmentse1
- Outcome
- carbohydrate statuse1
- Direction
- improvede1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Tea ( Camellia sinensis ) Plants”
e1“Tea plants are well-adapted to NH(4+)-rich environments by exhibiting a high capacity for NH4+ assimilation in their roots, reflected in strongly increased key enzyme activities and improved carbohydrate status”
Claim · model-written summary
Poor tea growth with NO3- was largely associated with inefficient absorption of this N source.
- Taxon
- Camellia sinensisCamellia sinensist0
- Treatment
- NO3-e1
- Outcome
- poor plant growthe1
- Qualifier
- inefficient absorption of this N sourcee1
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Tea ( Camellia sinensis ) Plants”
e1“The poor plant growth with NO3- was largely associated with inefficient absorption of this N source”
Claim · model-written summary
Decreased tea growth under inappropriate external pH corresponded with declining N absorption.
- Taxon
- Camellia sinensisCamellia sinensist0
- Treatment
- inappropriate external pHe1
- Outcome
- growthe1
- Direction
- Decreasede1
- Qualifier
- corresponded well with the declining absorption of nitrogene1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Tea ( Camellia sinensis ) Plants”
e1“Decreased growth caused by inappropriate external pH corresponded well with the declining absorption of nitrogen”
The same questions in other papers
nitrogen · physiology: enzyme activity · Camellia sinensis (black tea)Positive and negative results
2 in the opposite direction
- positive
- positive
ph · growth · Camellia sinensis (black tea)Positive and negative results
1 paper in the same direction as this paper · 1 in the opposite direction
- positive
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nitrogen · nutrient: content · Camellia sinensis (black tea)Positive and negative results
3 papers in the same direction as this paper · 7 in the opposite direction
- positive
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7 papers more in this group
See all 11 papers →ph · physiology: gas exchange · Camellia sinensis (black tea)Results agree
1 paper in the same direction as this paper
- no effect
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.