Abstract
Barley ( H ordeum vulgare ) was grown in different climatic environments with elevated [ CO 2 ] (700 vs 385 ppm), [ O 3 ] (60/90 vs 20 ppb) and temperature (24/19 vs 19/12° C day/night) as single factors and in combinations, to evaluate the impact of these climatic factors on photosynthesis and susceptibility to powdery mildew and spot blotch disease. No significant increase in net CO 2 assimilation rate was observed in barley grown under elevated [ CO 2 ] at ambient temperature. However, this rate was positively stimulated under elevated temperature together with a slightly higher potential quantum efficiency of PSII , both at ambient and elevated [ CO 2 ], suggesting that photosynthesis was not limited by [ CO 2 ] at ambient temperature. When growing under elevated temperature or [ O 3 ], infection by the biotrophic powdery mildew fungus decreased, whereas disease symptoms and growth of the toxin‐secreting hemibiotrophic spot blotch fungus increased compared to ambient conditions, implying that climate‐induced changes in disease severity could be linked to the trophic lifestyle of the pathogens. Elevated [ CO 2 ] decreased powdery mildew infection but had no effect on spot blotch disease compared to ambient condition. However, the effect of elevated [ CO 2 ], [ O 3 ] and temperature did not act in an additive manner when combined. This led to a surprising disease development in the combination treatments, where powdery mildew infection increased despite the individual reducing effect of the climatic factors, and spot blotch disease decreased despite the individual promoting effect of temperature and ozone, emphasizing the importance of conducting multifactorial experiments when evaluating the potential effects of climate change.
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 10
Claim · model-written summary
Elevated carbon dioxide did not significantly increase net assimilation at ambient temperature.
- Taxon
- barley
.jpg?width=60)
Hordeum vulgaree0 - Treatment
- elevated [ CO 2 ]e0
- Outcome
- net CO 2 assimilation ratee0
- Direction
- No significant increasee0
- Comparator
- ambient temperaturee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
.jpg?width=500)
Verbatim
e0“No significant increase in net CO 2 assimilation rate was observed in barley grown under elevated [ CO 2 ] at ambient temperature”
Claim · model-written summary
Elevated temperature stimulated net assimilation.
- Treatment
- elevated temperaturee0
- Outcome
- this ratee0
- Direction
- positively stimulatede0
- Comparator
- ambiente0
Not reportedTaxon
Verbatim
e0“this rate was positively stimulated under elevated temperature together with a slightly higher potential quantum efficiency of PSII , both at ambient and elevated [ CO 2 ]”
Claim · model-written summary
Elevated temperature slightly raised potential quantum efficiency of PSII.
- Treatment
- elevated temperaturee0
- Outcome
- potential quantum efficiency of PSIIe0
- Direction
- highere0
- Comparator
- ambiente0
Not reportedTaxon
Verbatim
e0“under elevated temperature together with a slightly higher potential quantum efficiency of PSII , both at ambient and elevated [ CO 2 ]”
Claim · model-written summary
Elevated temperature reduced powdery mildew infection.
- Treatment
- elevated temperaturee0
- Interactor
- powdery mildew funguse0pathogen
- Outcome
- infection by the biotrophic powdery mildew funguse0
- Direction
- decreasede0
Not reportedTaxonComparator
Verbatim
e0“When growing under elevated temperature or [ O 3 ], infection by the biotrophic powdery mildew fungus decreased”
Claim · model-written summary
Elevated ozone reduced powdery mildew infection.
- Treatment
- [ O 3 ]e0
- Interactor
- powdery mildew funguse0pathogen
- Outcome
- infection by the biotrophic powdery mildew funguse0
- Direction
- decreasede0
Not reportedTaxonComparator
Verbatim
e0“When growing under elevated temperature or [ O 3 ], infection by the biotrophic powdery mildew fungus decreased”
Claim · model-written summary
Elevated temperature increased spot blotch disease symptoms and fungal growth.
- Interactor
- spot blotch funguse0pathogen
- Outcome
- disease symptoms and growth of the toxin‐secreting hemibiotrophic spot blotch funguse0
- Direction
- increasede0
- Comparator
- ambient conditionse0
Not reportedTaxonTreatment
Verbatim
e0“disease symptoms and growth of the toxin‐secreting hemibiotrophic spot blotch fungus increased compared to ambient conditions”
Claim · model-written summary
Elevated carbon dioxide decreased powdery mildew infection.
- Treatment
- Elevated [ CO 2 ]e0
- Interactor
- powdery mildewe0pathogen
- Outcome
- powdery mildew infectione0
- Direction
- decreasede0
- Comparator
- ambient conditione0
Not reportedTaxon
Verbatim
e0“Elevated [ CO 2 ] decreased powdery mildew infection but had no effect on spot blotch disease compared to ambient condition”
Claim · model-written summary
Elevated carbon dioxide had no effect on spot blotch disease.
- Treatment
- Elevated [ CO 2 ]e0
- Interactor
- spot blotche0pathogen
- Outcome
- spot blotch diseasee0
- Direction
- had no effecte0
- Comparator
- ambient conditione0
Not reportedTaxon
Verbatim
e0“Elevated [ CO 2 ] decreased powdery mildew infection but had no effect on spot blotch disease compared to ambient condition”
Claim · model-written summary
Combined climate treatments increased powdery mildew infection despite individual reductions.
- Treatment
- climatic factorse0
- Interactor
- powdery mildewe0pathogen
- Outcome
- powdery mildew infectione0
- Direction
- increasede0
Not reportedTaxonComparator
Verbatim
e0“powdery mildew infection increased despite the individual reducing effect of the climatic factors”
Claim · model-written summary
Combined climate treatments decreased spot blotch disease despite individual promoting effects.
- Treatment
- temperature and ozonee0
- Interactor
- spot blotche0pathogen
- Outcome
- spot blotch diseasee0
- Direction
- decreasede0
Not reportedTaxonComparator
Verbatim
e0“spot blotch disease decreased despite the individual promoting effect of temperature and ozone”
The same questions in other papers
co2 · physiology: photosynthesis · Hordeum vulgare (barley)Positive and negative results
7 papers in the same direction as this paper · 5 in the opposite direction
- positive
- positive
- positive
9 papers more in this group
See all 13 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.