Abstract
ABSTRACT Crown and root rot of tomato caused by Fusarium oxysporum f. sp. radicis-lycopersici is an increasing problem in Europe, Israel, Japan, and North America. The biocontrol agent Pseudomonas fluorescens strain CHA0 provides only moderate control of this disease. A one-time amendment of zinc EDTA at 33 mug of Zn(2+)/ml to hydroponic nutrient solution in soilless rockwool culture did not reduce disease when used alone, but did reduce disease by 25% in the presence of CHA0. In in vitro studies with the pathogen, zinc at concentrations as low as 10 mug/ml abolished production of the phytotoxin fusaric acid, a Fusarium pathogenicity factor, and increased production of microconidia over 100-fold, but reduced total biomass. Copper EDTA at 33 mug of Cu(2+)/ml had a similar effect as zinc on the pathogen in vitro; it reduced disease when used alone, and increased the biocontrol activity of CHA0 in soilless culture. Ammonium-molybdate neither improved the biocontrol activity of CHA0 nor affected production of fusaric acid or microconidia. Strain CHA0 did not degrade fusaric acid. Fusaric acid at concentrations as low as 0.12 mug/ml repressed production by CHA0 of the antibiotic 2,4-diacetylphloroglucinol, a key factor in the biocontrol activity of this strain. Production of pyoluteorin by CHA0 was also reduced, but production of hydrogen cyanide and protease was not affected, suggesting that fusaric acid affects biosynthesis at a regulatory level downstream of gacA and apdA genes. Fusaric acid did not affect the recovery of preformed antibiotics nor did it affect bacterial growth even at concentrations as high as 200 mug/ml. When microbial meta-bolite production was measured in the rockwool bioassay, zinc amendments reduced fusaric acid production and enhanced 2,4-diacetylphloro-glucinol production. We suggest that zinc, which did not alleviate the repression of antibiotic biosynthesis by fusaric acid, improved biocontrol activity by reducing fusaric acid production by the pathogen, which resulted in increased antibiotic production by the biocontrol agent. This demonstrates that pathogens can have a direct negative impact on the mechanism(s) of biocontrol agents.
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 17
Claim · model-written summary
Zinc EDTA amendment alone did not reduce tomato Fusarium disease.
- Taxon
- tomato
Solanum lycopersicume1 - Treatment
- zinc EDTA at 33 mug of Zn(2+)/mle2
- Interactor
- Fusarium oxysporum f. sp. radicis-lycopersici
Fusarium oxysporum f. sp. radicis-lycopersicie1pathogen - Outcome
- diseasee3
- Direction
- did not reducee3
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“Crown and root rot of tomato caused by Fusarium oxysporum f. sp. radicis-lycopersici”
e2“A one-time amendment of zinc EDTA at 33 mug of Zn(2+)/ml to hydroponic nutrient solution”
e3“did not reduce disease when used alone”
Claim · model-written summary
Zinc EDTA amendment in the presence of CHA0 reduced tomato Fusarium disease by 25%.
- Taxon
- tomatoSolanum lycopersicume1
- Treatment
- zinc EDTA at 33 mug of Zn(2+)/mle2
- Interactor
- Fusarium oxysporum f. sp. radicis-lycopersiciFusarium oxysporum f. sp. radicis-lycopersicie1pathogen
- Second interactor
- Pseudomonas fluorescens strain CHA0
.JPG?width=60)
Pseudomonas fluorescense5biocontrol_agent - Outcome
- diseasee4
- Direction
- did reducee4
- Value
- 25%e4
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
.JPG?width=500)
Verbatim
e1“Crown and root rot of tomato caused by Fusarium oxysporum f. sp. radicis-lycopersici”
e2“A one-time amendment of zinc EDTA at 33 mug of Zn(2+)/ml to hydroponic nutrient solution”
e4“did reduce disease by 25% in the presence of CHA0”
e5“The biocontrol agent Pseudomonas fluorescens strain CHA0”
Claim · model-written summary
Copper EDTA amendment alone reduced tomato Fusarium disease.
- Taxon
- tomatoSolanum lycopersicume1
- Treatment
- Copper EDTA at 33 mug of Cu(2+)/mle6
- Interactor
- Fusarium oxysporum f. sp. radicis-lycopersiciFusarium oxysporum f. sp. radicis-lycopersicie1pathogen
- Outcome
- diseasee7
- Direction
- reducede7
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“Crown and root rot of tomato caused by Fusarium oxysporum f. sp. radicis-lycopersici”
e6“Copper EDTA at 33 mug of Cu(2+)/ml”
e7“it reduced disease when used alone”
Claim · model-written summary
Copper EDTA amendment increased the biocontrol activity of CHA0 in soilless culture.
- Taxon
- tomatoSolanum lycopersicume1
- Treatment
- Copper EDTA at 33 mug of Cu(2+)/mle6
- Interactor
- Fusarium oxysporum f. sp. radicis-lycopersiciFusarium oxysporum f. sp. radicis-lycopersicie1pathogen
- Second interactor
- Pseudomonas fluorescens strain CHA0Pseudomonas fluorescense5biocontrol_agent
- Outcome
- biocontrol activity of CHA0e3
- Direction
- increasede3
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“Crown and root rot of tomato caused by Fusarium oxysporum f. sp. radicis-lycopersici”
e6“Copper EDTA at 33 mug of Cu(2+)/ml”
e3“increased the biocontrol activity of CHA0 in soilless culture”
e5“The biocontrol agent Pseudomonas fluorescens strain CHA0”
Claim · model-written summary
Copper EDTA had a similar effect on the pathogen in vitro as zinc.
- Taxon
- tomatoSolanum lycopersicume1
- Treatment
- Copper EDTA at 33 mug of Cu(2+)/mle6
- Interactor
- Fusarium oxysporum f. sp. radicis-lycopersiciFusarium oxysporum f. sp. radicis-lycopersicie1pathogen
- Outcome
- effecte3
- Direction
- similare3
- Comparator
- zince3
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“Crown and root rot of tomato caused by Fusarium oxysporum f. sp. radicis-lycopersici”
e6“Copper EDTA at 33 mug of Cu(2+)/ml”
e3“had a similar effect as zinc on the pathogen in vitro”
Claim · model-written summary
Zinc at 10 mug/ml abolished in vitro production of the phytotoxin fusaric acid by the pathogen.
- Taxon
- tomatoSolanum lycopersicume1
- Treatment
- zinc at concentrations as low as 10 mug/mle2
- Interactor
- Fusarium oxysporum f. sp. radicis-lycopersiciFusarium oxysporum f. sp. radicis-lycopersicie1pathogen
- Outcome
- production of the phytotoxin fusaric acide2
- Direction
- abolishede2
- Setting
- in vitroe3
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“Crown and root rot of tomato caused by Fusarium oxysporum f. sp. radicis-lycopersici”
e2“zinc at concentrations as low as 10 mug/ml abolished production of the phytotoxin fusaric acid”
e3“In in vitro studies with the pathogen”
Claim · model-written summary
Zinc at 10 mug/ml increased in vitro microconidia production by the pathogen over 100-fold.
- Taxon
- tomatoSolanum lycopersicume1
- Treatment
- zinc at concentrations as low as 10 mug/mle2
- Interactor
- Fusarium oxysporum f. sp. radicis-lycopersiciFusarium oxysporum f. sp. radicis-lycopersicie1pathogen
- Outcome
- production of microconidiae4
- Direction
- increasede4
- Value
- 100-folde4
- Setting
- in vitroe3
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“Crown and root rot of tomato caused by Fusarium oxysporum f. sp. radicis-lycopersici”
e2“zinc at concentrations as low as 10 mug/ml abolished production of the phytotoxin fusaric acid”
e3“In in vitro studies with the pathogen”
e4“increased production of microconidia over 100-fold”
Claim · model-written summary
Zinc at 10 mug/ml reduced in vitro total biomass of the pathogen.
- Taxon
- tomatoSolanum lycopersicume1
- Treatment
- zinc at concentrations as low as 10 mug/mle2
- Interactor
- Fusarium oxysporum f. sp. radicis-lycopersiciFusarium oxysporum f. sp. radicis-lycopersicie1pathogen
- Outcome
- total biomasse4
- Direction
- reducede4
- Setting
- in vitroe3
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“Crown and root rot of tomato caused by Fusarium oxysporum f. sp. radicis-lycopersici”
e2“zinc at concentrations as low as 10 mug/ml abolished production of the phytotoxin fusaric acid”
e3“In in vitro studies with the pathogen”
e4“but reduced total biomass”
Claim · model-written summary
Ammonium-molybdate neither improved the biocontrol activity of CHA0.
- Taxon
- tomatoSolanum lycopersicume1
- Treatment
- Ammonium-molybdatee2
- Interactor
- Fusarium oxysporum f. sp. radicis-lycopersiciFusarium oxysporum f. sp. radicis-lycopersicie1pathogen
- Second interactor
- CHA0e2biocontrol_agent
- Outcome
- biocontrol activity of CHA0e2
- Direction
- neither improvede2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“Crown and root rot of tomato caused by Fusarium oxysporum f. sp. radicis-lycopersici”
e2“Ammonium-molybdate neither improved the biocontrol activity of CHA0”
Claim · model-written summary
Ammonium-molybdate did not affect production of fusaric acid or microconidia.
- Taxon
- tomatoSolanum lycopersicume1
- Treatment
- Ammonium-molybdatee2
- Interactor
- Fusarium oxysporum f. sp. radicis-lycopersiciFusarium oxysporum f. sp. radicis-lycopersicie1pathogen
- Outcome
- production of fusaric acid or microconidiae3
- Direction
- nor affectede3
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“Crown and root rot of tomato caused by Fusarium oxysporum f. sp. radicis-lycopersici”
e2“Ammonium-molybdate neither improved the biocontrol activity of CHA0”
e3“nor affected production of fusaric acid or microconidia”
Claim · model-written summary
CHA0 did not degrade fusaric acid.
- Taxon
- tomatoSolanum lycopersicume1
- Interactor
- CHA0e2biocontrol_agent
- Outcome
- degrade fusaric acide2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“Crown and root rot of tomato caused by Fusarium oxysporum f. sp. radicis-lycopersici”
e2“Strain CHA0 did not degrade fusaric acid”
Claim · model-written summary
Fusaric acid at 0.12 mug/ml repressed production by CHA0 of the antibiotic 2,4-diacetylphloroglucinol.
- Taxon
- tomatoSolanum lycopersicume1
- Treatment
- Fusaric acid at concentrations as low as 0.12 mug/mle2
- Interactor
- CHA0e2biocontrol_agent
- Outcome
- production by CHA0 of the antibiotic 2,4-diacetylphloroglucinole2
- Direction
- repressede2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“Crown and root rot of tomato caused by Fusarium oxysporum f. sp. radicis-lycopersici”
e2“Fusaric acid at concentrations as low as 0.12 mug/ml repressed production by CHA0 of the antibiotic 2,4-diacetylphloroglucinol”
Claim · model-written summary
Fusaric acid did not affect recovery of preformed antibiotics.
- Taxon
- tomatoSolanum lycopersicume1
- Treatment
- Fusaric acide2
- Outcome
- recovery of preformed antibioticse2
- Direction
- did not affecte2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“Crown and root rot of tomato caused by Fusarium oxysporum f. sp. radicis-lycopersici”
e2“Fusaric acid did not affect the recovery of preformed antibiotics”
Claim · model-written summary
Fusaric acid did not affect bacterial growth even at 200 mug/ml.
- Taxon
- tomatoSolanum lycopersicume1
- Treatment
- Fusaric acide2
- Outcome
- bacterial growthe3
- Direction
- nor did it affecte3
- Value
- 200 mug/mle3
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“Crown and root rot of tomato caused by Fusarium oxysporum f. sp. radicis-lycopersici”
e2“Fusaric acid did not affect the recovery of preformed antibiotics”
e3“nor did it affect bacterial growth even at concentrations as high as 200 mug/ml”
Claim · model-written summary
Zinc amendments reduced fusaric acid production in the rockwool bioassay.
- Taxon
- tomatoSolanum lycopersicume1
- Treatment
- zinc amendmentse3
- Outcome
- fusaric acid productione3
- Direction
- reducede3
- Setting
- rockwool bioassaye2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“Crown and root rot of tomato caused by Fusarium oxysporum f. sp. radicis-lycopersici”
e2“When microbial meta-bolite production was measured in the rockwool bioassay”
e3“zinc amendments reduced fusaric acid production”
Claim · model-written summary
Zinc amendments enhanced 2,4-diacetylphloroglucinol production in the rockwool bioassay.
- Taxon
- tomatoSolanum lycopersicume1
- Treatment
- zinc amendmentse3
- Outcome
- 2,4-diacetylphloro-glucinol productione4
- Direction
- enhancede4
- Setting
- rockwool bioassaye2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“Crown and root rot of tomato caused by Fusarium oxysporum f. sp. radicis-lycopersici”
e2“When microbial meta-bolite production was measured in the rockwool bioassay”
e3“zinc amendments reduced fusaric acid production”
e4“enhanced 2,4-diacetylphloro-glucinol production”
Claim · model-written summary
Zinc improved biocontrol activity by reducing fusaric acid production by the pathogen, which increased antibiotic production by the biocontrol agent.
- Taxon
- tomatoSolanum lycopersicume1
- Compound
- fusaric acide2
- Outcome
- biocontrol activitye2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“Crown and root rot of tomato caused by Fusarium oxysporum f. sp. radicis-lycopersici”
e2“We suggest that zinc, which did not alleviate the repression of antibiotic biosynthesis by fusaric acid, improved biocontrol activity by reducing fusaric acid production by the pathogen”
The same questions in other papers
zinc atom · yield · Solanum lycopersicum (tomato)Results differ
43 papers in the same direction as this paper · 1 in the opposite direction
- negative
- positive
- positive
41 papers more in this group
See all 45 papers →Fusaric acid · disease · Solanum lycopersicum (tomato)Positive and negative results
1 paper in the same direction as this paper · 2 in the opposite direction
- positive
- positive
- negative
Fusaric acid · molecular: metabolites · Solanum lycopersicum (tomato)Results agree
1 paper in the same direction as this paper
- negative
other · yield · Solanum lycopersicum (tomato)Positive and negative results
116 papers in the same direction as this paper · 13 in the opposite direction
- no effect
- no effect
- no effect
126 papers more in this group
See all 130 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.