Abstract
Effects of CO 2 enrichment on photosynthesis and on dry matter allocation were examined in two tobacco ( Nicotiana tabaum L.) genotypes. Samsun and W38. Plants were grown from seed in controlled environment chambers at a photosynthetic photon flux density of 450 μmol m −2 s −1 . Averaged over the 9 day study, net photosynthesis rates were 14.2±0.5 and 13.0±0.4 μmol m −2 s −1 in elevated (70 Pa) and in ambient (35 Pal CO 2 air. respectively, when measured at the irradiance and CO 2 partial pressure employed for plant growth. However. photosynthesis rates of plants grown in elevated CO 2 were 50% less than those of the ambient controls on the last day of treatment, when measured al 70 Pa CO 2 air and an irradiance of 900 μmol m −2 s −1 Total plant dry weight and specific leaf weight were greater ( P < 0.051 in enriched‐CO 2 ‐grown than in ambient‐CO 2 ‐grown plants. Leaf starch, measured during the first hour of the photoperiod. increased over 7 days of treatment in elevaled‐CO 2 ‐grown but not in ambient‐CO 2 ‐grown plants. Ribulose 1.5‐bisphosphate carboxylase/oxygenase (Rubisco) activities of tobacco plants grown at 35 and 70 Pa CO 2 air were 58.5±4.5 and 48.5±3.7 umol m −2 s −1 . respectively, between days 0 and 9 of the study. Rubisco activation state. Rubisco protein concentration. soluble protein and total chlorophyll were unaffected by CO 2 enrichment. The above findings demonstrated that photosynthesis was down regulated in tobacco plants after 7 to 9 days of CO 2 enrichment at low photosynthetic photon flxu density, but less than at moderate irradiances.
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Claims 8
Claim · model-written summary
Averaged over the study, net photosynthesis rates were 14.2 and 13.0 under elevated and ambient CO2 respectively.
- Taxon
- Nicotiana tabacum
Nicotiana tabacumt0 - Treatment
- elevated (70 Pa)e2
- Outcome
- net photosynthesis ratese1
- Value
- 14.2±0.5 and 13.0±0.4e1
- Comparator
- ambient (35 Pal CO 2 aire2
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Responses of Nicotiana tabacum to CO2 enrichment”
e1“net photosynthesis rates were 14.2±0.5 and 13.0±0.4”
e2“in elevated (70 Pa) and in ambient (35 Pal CO 2 air”
Claim · model-written summary
Photosynthesis rates of tobacco grown in elevated CO2 were 50% lower than in ambient controls on the last day of treatment.
- Taxon
- Nicotiana tabacumNicotiana tabacumt0
- Treatment
- elevated CO 2e3
- Outcome
- photosynthesis ratese3
- Direction
- lesse3
- Value
- 50%e3
- Qualifier
- on the last day of treatmente3
- Comparator
- ambient controlse3
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Responses of Nicotiana tabacum to CO2 enrichment”
e3“photosynthesis rates of plants grown in elevated CO 2 were 50% less than those of the ambient controls on the last day of treatment”
Claim · model-written summary
Total plant dry weight and specific leaf weight are greater in enriched-CO2-grown than in ambient-CO2-grown tobacco plants.
- Taxon
- Nicotiana tabacumNicotiana tabacumt0
- Treatment
- enriched‐CO 2 ‐growne5
- Outcome
- total plant dry weight and specific leaf weighte4
- Direction
- greatere4
- Comparator
- ambient‐CO 2 ‐grown plantse5
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Responses of Nicotiana tabacum to CO2 enrichment”
e4“Total plant dry weight and specific leaf weight were greater”
e5“enriched‐CO 2 ‐grown than in ambient‐CO 2 ‐grown plants”
Claim · model-written summary
Leaf starch increased over 7 days of treatment in elevated-CO2-grown tobacco but not in ambient-CO2-grown tobacco.
- Taxon
- Nicotiana tabacumNicotiana tabacumt0
- Treatment
- 7 days of treatmente6
- Outcome
- Leaf starche6
- Direction
- increasede6
- Comparator
- ambient‐CO 2 ‐grown plantse6
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Responses of Nicotiana tabacum to CO2 enrichment”
e6“Leaf starch, measured during the first hour of the photoperiod. increased over 7 days of treatment in elevaled‐CO 2 ‐grown but not in ambient‐CO 2 ‐grown plants”
Claim · model-written summary
Rubisco activity of tobacco is lower at 70 Pa CO2 than at 35 Pa CO2.
- Taxon
- Nicotiana tabacumNicotiana tabacumt0
- Treatment
- 70 Pa CO 2 aire7
- Gene
- Rubiscoe7
- Outcome
- activitiese7
- Direction
- lowerinferrede7
- Value
- 58.5±4.5 and 48.5±3.7e7
- Comparator
- 35 and 70 Pa CO 2 aire7
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Responses of Nicotiana tabacum to CO2 enrichment”
e7“(Rubisco) activities of tobacco plants grown at 35 and 70 Pa CO 2 air were 58.5±4.5 and 48.5±3.7”
Claim · model-written summary
Rubisco activation state and Rubisco protein concentration are unaffected by CO2 enrichment in tobacco.
- Taxon
- Nicotiana tabacumNicotiana tabacumt0
- Treatment
- CO 2 enrichmente1
- Outcome
- Rubisco activation state. Rubisco protein concentratione1
- Direction
- unaffectede1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Responses of Nicotiana tabacum to CO2 enrichment”
e1“Rubisco activation state. Rubisco protein concentration. soluble protein and total chlorophyll were unaffected by CO 2 enrichment”
Claim · model-written summary
Soluble protein and total chlorophyll in tobacco are unaffected by CO2 enrichment.
- Taxon
- Nicotiana tabacumNicotiana tabacumt0
- Treatment
- CO 2 enrichmente1
- Outcome
- soluble protein and total chlorophylle1
- Direction
- unaffectede1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Responses of Nicotiana tabacum to CO2 enrichment”
e1“Rubisco activation state. Rubisco protein concentration. soluble protein and total chlorophyll were unaffected by CO 2 enrichment”
Claim · model-written summary
Photosynthesis was down regulated in tobacco after 7 to 9 days of CO2 enrichment at low photon flux density, but less than at moderate irradiances.
- Taxon
- Nicotiana tabacumNicotiana tabacumt0
- Treatment
- 7 to 9 days of CO 2 enrichment at low photosynthetic photon flxu densitye1
- Outcome
- photosynthesise1
- Direction
- down regulatede1
- Qualifier
- but less than at moderate irradiancese1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Responses of Nicotiana tabacum to CO2 enrichment”
e1“photosynthesis was down regulated in tobacco plants after 7 to 9 days of CO 2 enrichment at low photosynthetic photon flxu density, but less than at moderate irradiances”
The same questions in other papers
co2 · physiology: photosynthesis · Nicotiana tabacum (tobacco)Positive and negative results
5 papers in the same direction as this paper · 10 in the opposite direction
- negative
- positive
- positive
12 papers more in this group
See all 16 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.