Abstract
The physiological, stomatal and ultrastructural responses to ozone and drought of ozone‐sensitive and more ozone‐tolerant birch ( Betula pendula Roth.) clones were studied singly and in combination, in a high‐stress chamber experiment and in a low‐stress open‐field experiment. In the chamber experiment, well watered (WW), moderately watered (MW) or drought‐stressed (DS) saplings were exposed for 36 d to 0 or 130 nmol mol ∠1 ozone. In the open‐field experiment, well watered or drought‐stressed saplings were grown for one growing season in ambient air or exposed to 1·8 × ambient ozone. Drought stress reduced growth rate, stomatal conductance, stomatal density and the proportion of starch and thylakoids in chloroplasts, but stimulated net photosynthesis, Rubisco and chlorophyll quantity at the end of the growing season, and increased the size and density of plastoglobuli. Ozone fumigations caused more variable, clone‐ and exposure‐dependent responses in growth, decreased stomatal conductance and net photosynthesis, an increased number of stomata, visible and ultrastructural chloroplast injuries, and enhanced autumn yellowing of the leaves. Ozone‐induced changes in plastoglobuli, starch and thylakoids resembled drought responses. The two experiments revealed that, depending on the experimental conditions and the variable, the response to drought and ozone stress can be independent, additive or interactive. Drought protected the plants from ozone injuries under high‐stress conditions in the chamber experiment. In the low‐stress, open‐field experiment, however, enhanced ozone damage was observed in birch saplings grown under restricted water supply.
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 12
Claim · model-written summary
Drought stress reduced growth rate, stomatal conductance and stomatal density of birch.
- Taxon
- Betula pendula
Betula pendulat1 - Treatment
- Drought stresse0
- Outcome
- growth rate, stomatal conductance, stomatal densitye0
- Direction
- reducede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t1“in birch (Betula pendula Roth.) are modified by water stress”
e0“Drought stress reduced growth rate, stomatal conductance, stomatal density and the proportion of starch and thylakoids in chloroplasts, but stimulated net photosynthesis, Rubisco and chlorophyll quantity at the end of the growing season, and increased the size and density of plastoglobuli”
Claim · model-written summary
Drought stress reduced the proportion of starch and thylakoids in birch chloroplasts.
- Taxon
- Betula pendulaBetula pendulat1
- Treatment
- Drought stresse0
- Outcome
- proportion of starch and thylakoids in chloroplastse0
- Direction
- reducede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t1“in birch (Betula pendula Roth.) are modified by water stress”
e0“Drought stress reduced growth rate, stomatal conductance, stomatal density and the proportion of starch and thylakoids in chloroplasts, but stimulated net photosynthesis, Rubisco and chlorophyll quantity at the end of the growing season, and increased the size and density of plastoglobuli”
Claim · model-written summary
Drought stress stimulated net photosynthesis, Rubisco and chlorophyll quantity of birch at the end of the growing season.
- Taxon
- Betula pendulaBetula pendulat1
- Treatment
- Drought stresse0
- Outcome
- net photosynthesis, Rubisco and chlorophyll quantitye0
- Direction
- stimulatede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t1“in birch (Betula pendula Roth.) are modified by water stress”
e0“Drought stress reduced growth rate, stomatal conductance, stomatal density and the proportion of starch and thylakoids in chloroplasts, but stimulated net photosynthesis, Rubisco and chlorophyll quantity at the end of the growing season, and increased the size and density of plastoglobuli”
Claim · model-written summary
Drought stress increased the size and density of plastoglobuli in birch chloroplasts.
- Taxon
- Betula pendulaBetula pendulat1
- Treatment
- Drought stresse0
- Outcome
- size and density of plastoglobulie0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t1“in birch (Betula pendula Roth.) are modified by water stress”
e0“Drought stress reduced growth rate, stomatal conductance, stomatal density and the proportion of starch and thylakoids in chloroplasts, but stimulated net photosynthesis, Rubisco and chlorophyll quantity at the end of the growing season, and increased the size and density of plastoglobuli”
Claim · model-written summary
Ozone fumigation decreased stomatal conductance and net photosynthesis of birch.
- Taxon
- Betula pendulaBetula pendulat1
- Treatment
- Ozone fumigationse2
- Outcome
- stomatal conductance and net photosynthesise1
- Direction
- decreasede1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t1“in birch (Betula pendula Roth.) are modified by water stress”
e1“decreased stomatal conductance and net photosynthesis, an increased number of stomata, visible and ultrastructural chloroplast injuries, and enhanced autumn yellowing of the leaves”
e2“Ozone fumigations caused”
Claim · model-written summary
Ozone fumigation increased the number of stomata of birch.
- Taxon
- Betula pendulaBetula pendulat1
- Treatment
- Ozone fumigationse2
- Outcome
- number of stomatae1
- Direction
- increasede1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t1“in birch (Betula pendula Roth.) are modified by water stress”
e1“decreased stomatal conductance and net photosynthesis, an increased number of stomata, visible and ultrastructural chloroplast injuries, and enhanced autumn yellowing of the leaves”
e2“Ozone fumigations caused”
Claim · model-written summary
Ozone fumigation caused visible and ultrastructural chloroplast injuries in birch.
- Taxon
- Betula pendulaBetula pendulat1
- Treatment
- Ozone fumigationse2
- Outcome
- chloroplast injuriese1
Not reportedComparatorDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t1“in birch (Betula pendula Roth.) are modified by water stress”
e1“decreased stomatal conductance and net photosynthesis, an increased number of stomata, visible and ultrastructural chloroplast injuries, and enhanced autumn yellowing of the leaves”
e2“Ozone fumigations caused”
Claim · model-written summary
Ozone fumigation enhanced autumn yellowing of birch leaves.
- Taxon
- Betula pendulaBetula pendulat1
- Treatment
- Ozone fumigationse2
- Outcome
- autumn yellowing of the leavese1
- Direction
- enhancede1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t1“in birch (Betula pendula Roth.) are modified by water stress”
e1“decreased stomatal conductance and net photosynthesis, an increased number of stomata, visible and ultrastructural chloroplast injuries, and enhanced autumn yellowing of the leaves”
e2“Ozone fumigations caused”
Claim · model-written summary
Ozone-induced changes in plastoglobuli, starch and thylakoids resembled drought responses in birch.
- Taxon
- Betula pendulaBetula pendulat1
- Outcome
- changes in plastoglobuli, starch and thylakoidse3
- Direction
- resemblede3
- Comparator
- drought responsese3
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t1“in birch (Betula pendula Roth.) are modified by water stress”
e3“changes in plastoglobuli, starch and thylakoids resembled drought responses”
Claim · model-written summary
The response of birch to drought and ozone stress can be independent, additive or interactive, depending on conditions.
- Taxon
- Betula pendulaBetula pendulat1
- Treatment
- drought and ozone stresse4
- Outcome
- response to drought and ozone stresse4
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t1“in birch (Betula pendula Roth.) are modified by water stress”
e4“The two experiments revealed that, depending on the experimental conditions and the variable, the response to drought and ozone stress can be independent, additive or interactive”
Claim · model-written summary
Drought protected birch from ozone injuries under high-stress chamber conditions.
- Taxon
- Betula pendulaBetula pendulat1
- Treatment
- Droughte5
- Outcome
- ozone injuriese5
- Direction
- protectede5
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t1“in birch (Betula pendula Roth.) are modified by water stress”
e5“Drought protected the plants from ozone injuries”
Claim · model-written summary
In the low-stress open-field experiment, drought-restricted birch saplings showed enhanced ozone damage.
- Taxon
- Betula pendulaBetula pendulat1
- Treatment
- restricted water supplye6
- Outcome
- ozone damagee6
- Direction
- enhancede6
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t1“in birch (Betula pendula Roth.) are modified by water stress”
e6“enhanced ozone damage was observed in birch saplings grown under restricted water supply”
The same questions in other papers
ozone · physiology: gas exchange · Betula pendula (white birch)Results differ
6 papers in the same direction as this paper · 1 in the opposite direction
- negative
- negative
- negative
4 papers more in this group
See all 8 papers →ozone · disease · Betula pendula (white birch)Results agree
1 paper in the same direction as this paper
- negative
ozone · physiology: photosynthesis · Betula pendula (white birch)Results agree
4 papers in the same direction as this paper
- negative
- negative
- negative
1 paper more in this group
See all 5 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.