Abstract
FACE (Free-air Carbon Dioxide Enrichment) was used to study the effects of elevated CO2 on rice (Oryza sativa) growth, tissue C/N, N and P concentration and uptake at different development stages under two N and two P levels. Results showed that elevated CO2 increased dry matter accumulation in rice stem, ear and root. Leaf dry matter was increased at tillering stage and no significant effect was found at jointing, heading and ripening stages. N concentration of stem and leaf was decreased. Ear N concentration at heading stage was increased but was decreased at ripening stage. No significant effect was found on root N concentration at tillering stage but root N concentration at jointing, heading and ripening was decreased. Leaf P concentration at jointing, heading and ripening was increased but no significant effect was found on P concentration in stem, ear and root. C content in various tissues changed unremarkably and the ratio of C over N (C/N) was increased. Elevated CO2 significantly increased P uptake in aboveground tissues; and increased N uptake, but the difference was not statistically significant. N and P fertilization had no significant effect on various tissue dry biomass. Tissue N content at higher N fertilization was higher than at lower N fertilization but no such effect of P fertilization on tissue P content was found. At higher N fertilization, elevated CO2 increased the ratio of below-ground biomass over above-ground biomass at ripening stage. Possible reasons are discussed for the differences of tissue N and P content and the ratio of below-ground biomass over above-ground biomass between elevated and ambient atmospheric CO2 concentrations.
Abstract from the paper’s OpenAlex record, shown for indexing and research. Copyright remains with the authors or the publisher. Read at the source ↗
The text the model read, with the source record’s inline markup (italics, sub- and superscripts) rendered and its character entities decoded; quote offsets refer to the raw text.
Claims 18
Claim · model-written summary
Elevated CO2 increased stem, ear and root dry matter.
- Taxon
- rice
Oryza sativae0 - Treatment
- elevated CO2e0
- Outcome
- dry matter accumulation in rice stem, ear and roote0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“elevated CO2 increased dry matter accumulation in rice stem, ear and root.”
Claim · model-written summary
Elevated CO2 increased leaf dry matter at tillering.
- Taxon
- riceOryza sativae1
- Organ / stage
- tillering stagee0
- Outcome
- Leaf dry mattere0
- Direction
- increasede0
Not reportedTreatmentComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Leaf dry matter was increased at tillering stage”
e1“rice (Oryza sativa)”
Claim · model-written summary
Elevated CO2 had no significant effect on leaf dry matter at later stages.
- Taxon
- riceOryza sativae1
- Organ / stage
- jointing, heading and ripening stagese0
- Outcome
- effecte0
- Direction
- no significant effecte0
Not reportedTreatmentComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“no significant effect was found at jointing, heading and ripening stages.”
e1“rice (Oryza sativa)”
Claim · model-written summary
Stem and leaf N concentration decreased.
- Taxon
- riceOryza sativae1
- Outcome
- N concentration of stem and leafe0
- Direction
- decreasede0
Not reportedTreatmentComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“N concentration of stem and leaf was decreased.”
e1“rice (Oryza sativa)”
Claim · model-written summary
Ear N concentration increased at heading.
- Taxon
- riceOryza sativae1
- Organ / stage
- heading stagee0
- Outcome
- Ear N concentratione0
- Direction
- increasede0
Not reportedTreatmentComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Ear N concentration at heading stage was increased but was decreased at ripening stage.”
e1“rice (Oryza sativa)”
Claim · model-written summary
Ear N concentration decreased at ripening.
- Taxon
- riceOryza sativae1
- Organ / stage
- ripening stagee0
- Outcome
- Ear N concentratione0
- Direction
- decreasede0
Not reportedTreatmentComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Ear N concentration at heading stage was increased but was decreased at ripening stage.”
e1“rice (Oryza sativa)”
Claim · model-written summary
Root N concentration did not significantly change at tillering.
- Taxon
- riceOryza sativae1
- Organ / stage
- tillering stagee0
- Outcome
- root N concentratione0
- Direction
- No significant effecte0
Not reportedTreatmentComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“No significant effect was found on root N concentration at tillering stage”
e1“rice (Oryza sativa)”
Claim · model-written summary
Root N concentration decreased at jointing, heading and ripening.
- Taxon
- riceOryza sativae1
- Organ / stage
- jointing, heading and ripeninge0
- Outcome
- root N concentratione0
- Direction
- decreasede0
Not reportedTreatmentComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“root N concentration at jointing, heading and ripening was decreased.”
e1“rice (Oryza sativa)”
Claim · model-written summary
Leaf P concentration increased at jointing, heading and ripening.
- Taxon
- riceOryza sativae1
- Organ / stage
- jointing, heading and ripeninge0
- Outcome
- Leaf P concentratione0
- Direction
- increasede0
Not reportedTreatmentComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Leaf P concentration at jointing, heading and ripening was increased”
e1“rice (Oryza sativa)”
Claim · model-written summary
Stem, ear and root P concentrations had no significant effect.
- Taxon
- riceOryza sativae1
- Outcome
- P concentration in stem, ear and roote0
- Direction
- no significant effecte0
Not reportedTreatmentComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“no significant effect was found on P concentration in stem, ear and root.”
e1“rice (Oryza sativa)”
Claim · model-written summary
Tissue C content changed unremarkably.
- Taxon
- riceOryza sativae1
- Outcome
- C content in various tissuese0
- Direction
- changed unremarkablye0
Not reportedTreatmentComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“C content in various tissues changed unremarkably”
e1“rice (Oryza sativa)”
Claim · model-written summary
Tissue C/N ratio increased.
- Taxon
- riceOryza sativae1
- Outcome
- ratio of C over N (C/N)e0
- Direction
- increasede0
Not reportedTreatmentComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the ratio of C over N (C/N) was increased.”
e1“rice (Oryza sativa)”
Claim · model-written summary
Elevated CO2 significantly increased aboveground P uptake.
- Taxon
- riceOryza sativae1
- Treatment
- Elevated CO2e0
- Outcome
- P uptake in aboveground tissuese0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Elevated CO2 significantly increased P uptake in aboveground tissues”
e1“rice (Oryza sativa)”
Claim · model-written summary
Elevated CO2 increased N uptake without statistical significance.
- Taxon
- riceOryza sativae1
- Outcome
- N uptakee0
- Direction
- increasede0
Not reportedTreatmentComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“increased N uptake, but the difference was not statistically significant.”
e1“rice (Oryza sativa)”
Claim · model-written summary
N and P fertilization had no significant effect on tissue dry biomass.
- Taxon
- riceOryza sativae1
- Treatment
- N and P fertilizatione0
- Outcome
- various tissue dry biomasse0
- Direction
- no significant effecte0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“N and P fertilization had no significant effect on various tissue dry biomass.”
e1“rice (Oryza sativa)”
Claim · model-written summary
Higher N fertilization increased tissue N content.
- Taxon
- riceOryza sativae1
- Treatment
- higher N fertilizatione0
- Outcome
- Tissue N contente0
- Direction
- highere0
- Comparator
- lower N fertilizatione0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Tissue N content at higher N fertilization was higher than at lower N fertilization”
e1“rice (Oryza sativa)”
Claim · model-written summary
P fertilization did not similarly affect tissue P content.
- Taxon
- riceOryza sativae1
- Treatment
- P fertilizatione0
- Outcome
- tissue P contente0
- Direction
- no such effecte0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“no such effect of P fertilization on tissue P content was found.”
e1“rice (Oryza sativa)”
Claim · model-written summary
Under higher N fertilization, elevated CO2 increased the belowground to aboveground biomass ratio at ripening.
- Taxon
- riceOryza sativae1
- Organ / stage
- ripening stagee0
- Treatment
- elevated CO2e0
- Outcome
- ratio of below-ground biomass over above-ground biomasse0
- Direction
- increasede0
- Qualifier
- higher N fertilizatione0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“At higher N fertilization, elevated CO2 increased the ratio of below-ground biomass over above-ground biomass at ripening stage.”
e1“rice (Oryza sativa)”
The same questions in other papers
co2 · yield · Oryza sativa (rice)Positive and negative results
130 papers in the same direction as this paper · 28 in the opposite direction
- negative
- negative
- negative
155 papers more in this group
See all 159 papers →phosphorus · growth · Oryza sativa (rice)Positive and negative results
32 papers in the same direction as this paper · 133 in the opposite direction
- positive
- positive
- positive
162 papers more in this group
See all 166 papers →nitrogen · growth · Oryza sativa (rice)Positive and negative results
108 papers in the same direction as this paper · 402 in the opposite direction
- positive
- positive
- positive
507 papers more in this group
See all 511 papers →fertilization · growth · Oryza sativa (rice)Positive and negative results
88 papers in the same direction as this paper · 670 in the opposite direction
- positive
- positive
- positive
755 papers more in this group
See all 759 papers →fertilization · nutrient: content · Oryza sativa (rice)Positive and negative results
60 papers in the same direction as this paper · 932 in the opposite direction
- positive
- positive
- positive
989 papers more in this group
See all 993 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.