Abstract
Tomato ( Lycopersicon esculentum L.) production in the San Joaquin Valley (SJV) of California is challenged by air pollution and weeds. Differential ozone (O 3 ) tolerance of tomato cultivars and weed species may alter crop–weed competition. A study was conducted in open top chambers (OTCs) at the Kearney Research and Extension Center, Parlier, CA, to assess O 3 impacts on competition between tomato and a C 4 weed, yellow nutsedge ( Cyperus esculentus L.). Processing tomato (cv. HD 8892 and EMP 113) and nutsedge (locally collected biotypes) were grown in pots for 4 to 8 wk. Population ratios ranged from a tomato plant alone (0:1) to a nutsedge plant alone (1:0), and included 1:1, 2:1, and 3:1. Ozone exposures were to 12 h means of 19.8, 78.0, and 142.3 nL/L. Chlorophyll content of leaves of tomato and nutsedge was reduced with increasing O 3 Carbon assimilation was reduced in nutsedge but not in tomato. Root respiration was not affected in either species. Tomato main stem length, shoot, and root biomass declined at the highest O 3 concentration under all levels of nutsedge competition. Nutsedge was much less affected. In the absence of O 3 exposure, interspecific competition (all population ratios combined) reduced tomato and nutsedge shoot and root biomass. Tomato was more sensitive to O 3 than nutsedge, but nutsedge was more sensitive to competition than was tomato. Nutsedge allocated greater resources to reproductive structures (tubers) at the highest O 3 exposure. As nutsedge reduced tomato productivity under low and moderate O 3 concentrations, it may become even more difficult to control, exert greater competitiveness, and colonize fields more rapidly because of greater tuber production, in projected near‐future environments. Under conditions of greatly increasing ambient O 3 concentrations, nutsedge may become less competitive because of its sensitivity to O 3
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 11
Claim · model-written summary
Chlorophyll content of tomato and nutsedge leaves was reduced with increasing ozone.
- Taxon
- tomato
Solanum lycopersicume1 - Treatment
- increasing O 3e1
- Interactor
- nutsedgee1weed
- Outcome
- Chlorophyll content of leavese1
- Direction
- reducede1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Ozone Impacts on Competition between Tomato and Yellow Nutsedge”
e1“Chlorophyll content of leaves of tomato and nutsedge was reduced with increasing O 3”
Claim · model-written summary
Carbon assimilation was reduced in nutsedge under ozone.
- Taxon
- tomatoSolanum lycopersicume2
- Treatment
- Ozonet0
- Interactor
- nutsedgee2weed
- Outcome
- Carbon assimilatione2
- Direction
- reducede2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Ozone Impacts on Competition between Tomato and Yellow Nutsedge”
e2“Carbon assimilation was reduced in nutsedge but not in tomato”
Claim · model-written summary
Carbon assimilation was not reduced in tomato under ozone.
- Taxon
- tomatoSolanum lycopersicume2
- Treatment
- Ozonet0
- Outcome
- Carbon assimilatione2
- Direction
- no_changeinferrede2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Ozone Impacts on Competition between Tomato and Yellow Nutsedge”
e2“Carbon assimilation was reduced in nutsedge but not in tomato”
Claim · model-written summary
Root respiration was not affected by ozone in either species.
- Taxon
- TomatoSolanum lycopersicumt0
- Treatment
- Ozonet0
- Outcome
- Root respiratione3
- Direction
- not affectede3
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Ozone Impacts on Competition between Tomato and Yellow Nutsedge”
e3“Root respiration was not affected in either species”
Claim · model-written summary
Tomato main stem length, shoot and root biomass declined at the highest ozone concentration under all levels of nutsedge competition.
- Taxon
- TomatoSolanum lycopersicume4
- Treatment
- highest O 3 concentratione4
- Interactor
- nutsedgee4weed
- Outcome
- main stem length, shoot, and root biomasse4
- Direction
- declinede4
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Ozone Impacts on Competition between Tomato and Yellow Nutsedge”
e4“Tomato main stem length, shoot, and root biomass declined at the highest O 3 concentration under all levels of nutsedge competition”
Claim · model-written summary
Nutsedge was much less affected by ozone than tomato.
- Taxon
- TomatoSolanum lycopersicumt0
- Treatment
- Ozonet0
- Interactor
- Nutsedgee5weed
- Outcome
- Nutsedge was much less affectede5
- Direction
- much lesse5
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Ozone Impacts on Competition between Tomato and Yellow Nutsedge”
e5“Nutsedge was much less affected”
Claim · model-written summary
In the absence of ozone, interspecific competition reduced tomato and nutsedge shoot and root biomass.
- Taxon
- tomatoSolanum lycopersicume6
- Treatment
- interspecific competitione6
- Interactor
- nutsedgee6weed
- Outcome
- shoot and root biomasse6
- Direction
- reducede6
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Ozone Impacts on Competition between Tomato and Yellow Nutsedge”
e6“In the absence of O 3 exposure, interspecific competition (all population ratios combined) reduced tomato and nutsedge shoot and root biomass”
Claim · model-written summary
Tomato was more sensitive to ozone than nutsedge.
- Taxon
- TomatoSolanum lycopersicume7
- Treatment
- O 3e7
- Outcome
- sensitive to O 3e7
- Direction
- more sensitivee7
- Comparator
- nutsedgee7
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Ozone Impacts on Competition between Tomato and Yellow Nutsedge”
e7“Tomato was more sensitive to O 3 than nutsedge”
Claim · model-written summary
Nutsedge was more sensitive to competition than tomato.
- Taxon
- tomatoSolanum lycopersicume0
- Treatment
- competitione0
- Interactor
- nutsedgee0weed
- Outcome
- sensitive to competitione0
- Direction
- more sensitivee0
- Comparator
- tomatoe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Ozone Impacts on Competition between Tomato and Yellow Nutsedge”
e0“nutsedge was more sensitive to competition than was tomato”
Claim · model-written summary
Nutsedge allocated greater resources to reproductive structures (tubers) at the highest ozone exposure.
- Taxon
- TomatoSolanum lycopersicumt0
- Organ / stage
- tuberse1
- Treatment
- highest O 3 exposuree1
- Interactor
- Nutsedgee1weed
- Outcome
- resources to reproductive structurese1
- Direction
- greatere1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Ozone Impacts on Competition between Tomato and Yellow Nutsedge”
e1“Nutsedge allocated greater resources to reproductive structures (tubers) at the highest O 3 exposure”
Claim · model-written summary
Nutsedge may become even more difficult to control in projected near-future ozone environments where it reduces tomato productivity.
- Taxon
- tomatoSolanum lycopersicume2
- Treatment
- low and moderate O 3 concentrationse2
- Interactor
- nutsedgee2weed
- Outcome
- difficult to controle2
- Direction
- even more difficulte2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Ozone Impacts on Competition between Tomato and Yellow Nutsedge”
e2“As nutsedge reduced tomato productivity under low and moderate O 3 concentrations, it may become even more difficult to control”
The same questions in other papers
ozone · growth · Solanum lycopersicum (tomato)Results differ
12 papers in the same direction as this paper · 4 in the opposite direction
- negative
- negative
- negative
13 papers more in this group
See all 17 papers →ozone · physiology: photosynthesis · Solanum lycopersicum (tomato)Positive and negative results
2 papers in the same direction as this paper · 3 in the opposite direction
- negative
- negative
- negative
2 papers more in this group
See all 6 papers →competition · growth · Solanum lycopersicum (tomato)Results agree
3 papers in the same direction as this paper
- no effect
- negative
- 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.