Abstract
In mycorrhizal symbioses, susceptibility of a host plant to infection by fungi is influenced by environmental factors, especially the availability of soil phosphorus. This study describes morphological and biochemical details of interactions between a vesicular-arbuscular mycorrhizal (VAM) fungus and potato (Solanum tuberosum L. cv Russet Burbank) plants, with a particular focus on the physiological basis for P-induced resistance of roots to infection. Root infection by the VAM fungus Glomus fasciculatum ([Thaxt. sensu Gerdemann] Gerdemann and Trappe) was extensive for plants grown with low abiotic P supply, and plant biomass accumulation was enhanced by the symbiosis. The capacity of excised roots from P-deficient plants to produce ethylene in the presence or absence of exogenous 1-amino cyclopropane-1-carboxylic acid (ACC) was markedly reduced by VAM infection. This apparent inhibition of ACC oxidase (ACC(ox)) activity was localized to areas containing infected roots, as demonstrated in split-root studies. Furthermore, leachate from VAM roots contained a potent water-soluble inhibitor of ethylene generation from exogenous ACC by nonmycorrhizal (NM) roots. The leachate from VAM-infected roots had a higher concentration of phenolics, relative to that from NM roots. Moreover, the rates of ethylene formation and phenolic concentration in leachates from VAM roots were inversely correlated, suggesting that this inhibitor may be of a phenolic nature. The specific activity of extracellular peroxidase recovered in root leachates was not stimulated by VAM infection, although activity on a fresh weight basis was significantly enhanced, reflecting the fact that VAM roots had higher protein content than NM roots. Polyphenol oxidase activity of roots did not differ between NM and VAM roots. These results characterize the low resistance response of P-deficient plants to VAM infection. When plants were grown with higher abiotic P supply, the relative benefit of the VAM symbiosis to plant growth decreased and root infection was lower. The in vivo ACC(ox) activity was also greater in roots of plants grown on high levels of P compared with those grown on low levels, although the influence of VAM infection was partially to counteract the nutritional effect of P on ACC(ox) activity. Similar to ACC(ox) activity, extracellular peroxidase activity of roots increased linearly with increasing abiotic P supply, thus indicating a greater potential for resistance to VAM infection. These findings suggest that VAM fungi may alter phenolic metabolism of roots so as to hinder ethylene production and the root's ability to invoke a defense response. Raising the abiotic P supply to plants at least partially restores the capacity of roots to produce ethylene and may, in this way, increase the root's resistance to VAM infection.
Abstract from the paper’s OpenAlex record; open copy licensed cc-by. 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 19
Claim · model-written summary
In potato, VAM infection markedly reduced the ability of excised roots from P-deficient plants to produce ethylene.
- Taxon
- potato
Solanum tuberosume0 - Material
- Russet Burbanke0
- Organ / stage
- excised rootse1
- Treatment
- VAM infectione1
- Interactor
- vesicular-arbuscular mycorrhizal (VAM) funguse0symbiont
- Outcome
- capacity of excised roots from P-deficient plants to produce ethylenee1
- Direction
- markedly reducede1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“a vesicular-arbuscular mycorrhizal (VAM) fungus and potato (Solanum tuberosum L. cv Russet Burbank) plants”
e1“The capacity of excised roots from P-deficient plants to produce ethylene in the presence or absence of exogenous 1-amino cyclopropane-1-carboxylic acid (ACC) was markedly reduced by VAM infection”
Claim · model-written summary
In potato under low abiotic P supply, the symbiosis with VAM fungus enhanced plant biomass accumulation.
- Taxon
- potatoSolanum tuberosume0
- Treatment
- symbiosise2
- Interactor
- Glomus fasciculatumRhizophagus fasciculatuse2symbiont
- Outcome
- plant biomass accumulatione2
- Direction
- enhancede2
- Qualifier
- plants grown with low abiotic P supplye2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“a vesicular-arbuscular mycorrhizal (VAM) fungus and potato (Solanum tuberosum L. cv Russet Burbank) plants”
e2“Root infection by the VAM fungus Glomus fasciculatum ([Thaxt. sensu Gerdemann] Gerdemann and Trappe) was extensive for plants grown with low abiotic P supply, and plant biomass accumulation was enhanced by the symbiosis”
Claim · model-written summary
Under low abiotic P supply, root infection by the VAM fungus was extensive in potato.
- Taxon
- potatoSolanum tuberosume0
- Treatment
- low abiotic P supplye2
- Interactor
- Glomus fasciculatumRhizophagus fasciculatuse2symbiont
- Outcome
- Root infectione2
- Direction
- extensivee2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“a vesicular-arbuscular mycorrhizal (VAM) fungus and potato (Solanum tuberosum L. cv Russet Burbank) plants”
e2“Root infection by the VAM fungus Glomus fasciculatum ([Thaxt. sensu Gerdemann] Gerdemann and Trappe) was extensive for plants grown with low abiotic P supply, and plant biomass accumulation was enhanced by the symbiosis”
Claim · model-written summary
With higher abiotic P supply, the relative benefit of the VAM symbiosis to potato growth decreased.
- Taxon
- potatoSolanum tuberosume0
- Treatment
- higher abiotic P supplye3
- Interactor
- VAMe3symbiont
- Outcome
- the relative benefit of the VAM symbiosis to plant growthe3
- Direction
- decreasede3
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“a vesicular-arbuscular mycorrhizal (VAM) fungus and potato (Solanum tuberosum L. cv Russet Burbank) plants”
e3“When plants were grown with higher abiotic P supply, the relative benefit of the VAM symbiosis to plant growth decreased and root infection was lower”
Claim · model-written summary
With higher abiotic P supply, root infection by the VAM fungus was lower in potato.
- Taxon
- potatoSolanum tuberosume0
- Treatment
- higher abiotic P supplye3
- Interactor
- VAMe3symbiont
- Outcome
- root infectione3
- Direction
- lowere3
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“a vesicular-arbuscular mycorrhizal (VAM) fungus and potato (Solanum tuberosum L. cv Russet Burbank) plants”
e3“When plants were grown with higher abiotic P supply, the relative benefit of the VAM symbiosis to plant growth decreased and root infection was lower”
Claim · model-written summary
The apparent inhibition of ACC oxidase activity in potato was localized to areas containing VAM-infected roots in split-root studies.
- Taxon
- potatoSolanum tuberosume0
- Organ / stage
- areas containing infected rootse4
- Gene
- ACC oxidase (ACC(ox))e4
- Outcome
- ACC oxidase (ACC(ox)) activitye4
- Direction
- inhibitione4
- Qualifier
- apparente4
- Setting
- split-root studiese4
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“a vesicular-arbuscular mycorrhizal (VAM) fungus and potato (Solanum tuberosum L. cv Russet Burbank) plants”
e4“This apparent inhibition of ACC oxidase (ACC(ox)) activity was localized to areas containing infected roots, as demonstrated in split-root studies”
Claim · model-written summary
Leachate from VAM roots of potato contained a potent water-soluble inhibitor of ethylene generation from exogenous ACC.
- Taxon
- potatoSolanum tuberosume0
- Organ / stage
- leachate from VAM rootse5
- Interactor
- vesicular-arbuscular mycorrhizal (VAM) funguse0symbiont
- Outcome
- water-soluble inhibitor of ethylene generation from exogenous ACCe5
- Qualifier
- potente5
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“a vesicular-arbuscular mycorrhizal (VAM) fungus and potato (Solanum tuberosum L. cv Russet Burbank) plants”
e5“leachate from VAM roots contained a potent water-soluble inhibitor of ethylene generation from exogenous ACC by nonmycorrhizal (NM) roots”
Claim · model-written summary
Leachate from VAM-infected potato roots had a higher phenolic concentration than leachate from nonmycorrhizal roots.
- Taxon
- potatoSolanum tuberosume0
- Organ / stage
- leachatee6
- Treatment
- VAM-infected rootse6
- Outcome
- concentration of phenolicse6
- Direction
- highere6
- Comparator
- NM rootse6
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“a vesicular-arbuscular mycorrhizal (VAM) fungus and potato (Solanum tuberosum L. cv Russet Burbank) plants”
e6“The leachate from VAM-infected roots had a higher concentration of phenolics, relative to that from NM roots”
Claim · model-written summary
In potato, the rates of ethylene formation and phenolic concentration in VAM root leachates were inversely correlated.
- Taxon
- potatoSolanum tuberosume0
- Organ / stage
- leachates from VAM rootse7
- Outcome
- rates of ethylene formation and phenolic concentratione7
- Direction
- inversely correlatede7
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“a vesicular-arbuscular mycorrhizal (VAM) fungus and potato (Solanum tuberosum L. cv Russet Burbank) plants”
e7“the rates of ethylene formation and phenolic concentration in leachates from VAM roots were inversely correlated, suggesting that this inhibitor may be of a phenolic nature”
Claim · model-written summary
The VAM-induced inhibitor in potato leachates may be of a phenolic nature.
- Taxon
- potatoSolanum tuberosume0
- Compound
- phenolice7
- Outcome
- this inhibitore7
- Qualifier
- may be of a phenolic naturee7
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“a vesicular-arbuscular mycorrhizal (VAM) fungus and potato (Solanum tuberosum L. cv Russet Burbank) plants”
e7“the rates of ethylene formation and phenolic concentration in leachates from VAM roots were inversely correlated, suggesting that this inhibitor may be of a phenolic nature”
Claim · model-written summary
VAM infection did not stimulate the specific activity of extracellular peroxidase recovered in potato root leachates.
- Taxon
- potatoSolanum tuberosume0
- Organ / stage
- root leachatese1
- Treatment
- VAM infectione1
- Gene
- extracellular peroxidasee1
- Outcome
- specific activity of extracellular peroxidase recovered in root leachatese1
- Direction
- not stimulatede1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“a vesicular-arbuscular mycorrhizal (VAM) fungus and potato (Solanum tuberosum L. cv Russet Burbank) plants”
e1“The specific activity of extracellular peroxidase recovered in root leachates was not stimulated by VAM infection, although activity on a fresh weight basis was significantly enhanced, reflecting the fact that VAM roots had higher protein content than NM roots”
Claim · model-written summary
Activity of extracellular peroxidase on a fresh weight basis was significantly enhanced in VAM roots compared with NM roots of potato.
- Taxon
- potatoSolanum tuberosume0
- Treatment
- VAM rootse1
- Gene
- extracellular peroxidasee1
- Outcome
- activity on a fresh weight basise1
- Direction
- significantly enhancede1
- Comparator
- NM rootse1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“a vesicular-arbuscular mycorrhizal (VAM) fungus and potato (Solanum tuberosum L. cv Russet Burbank) plants”
e1“The specific activity of extracellular peroxidase recovered in root leachates was not stimulated by VAM infection, although activity on a fresh weight basis was significantly enhanced, reflecting the fact that VAM roots had higher protein content than NM roots”
Claim · model-written summary
VAM roots of potato had higher protein content than NM roots.
- Taxon
- potatoSolanum tuberosume0
- Treatment
- VAM rootse1
- Outcome
- protein contente1
- Direction
- highere1
- Comparator
- NM rootse1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“a vesicular-arbuscular mycorrhizal (VAM) fungus and potato (Solanum tuberosum L. cv Russet Burbank) plants”
e1“The specific activity of extracellular peroxidase recovered in root leachates was not stimulated by VAM infection, although activity on a fresh weight basis was significantly enhanced, reflecting the fact that VAM roots had higher protein content than NM roots”
Claim · model-written summary
Polyphenol oxidase activity of potato roots did not differ between NM and VAM roots.
- Taxon
- potatoSolanum tuberosume0
- Treatment
- VAM rootse1
- Gene
- Polyphenol oxidasee1
- Outcome
- Polyphenol oxidase activity of rootse1
- Direction
- did not differe1
- Comparator
- NMe1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“a vesicular-arbuscular mycorrhizal (VAM) fungus and potato (Solanum tuberosum L. cv Russet Burbank) plants”
e1“Polyphenol oxidase activity of roots did not differ between NM and VAM roots”
Claim · model-written summary
In potato roots, in vivo ACC(ox) activity was greater in plants grown on high levels of P than in those grown on low levels.
- Taxon
- potatoSolanum tuberosume0
- Organ / stage
- rootse1
- Treatment
- high levels of Pe1
- Gene
- ACC(ox)e1
- Outcome
- in vivo ACC(ox) activitye1
- Direction
- greatere1
- Comparator
- low levelse1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“a vesicular-arbuscular mycorrhizal (VAM) fungus and potato (Solanum tuberosum L. cv Russet Burbank) plants”
e1“The in vivo ACC(ox) activity was also greater in roots of plants grown on high levels of P compared with those grown on low levels, although the influence of VAM infection was partially to counteract the nutritional effect of P on ACC(ox) activity”
Claim · model-written summary
VAM infection partially counteracted the nutritional effect of P on ACC(ox) activity in potato.
- Taxon
- potatoSolanum tuberosume0
- Treatment
- VAM infectione1
- Interactor
- VAMe1symbiont
- Gene
- ACC(ox)e1
- Outcome
- nutritional effect of P on ACC(ox) activitye1
- Direction
- partially to counteracte1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“a vesicular-arbuscular mycorrhizal (VAM) fungus and potato (Solanum tuberosum L. cv Russet Burbank) plants”
e1“The in vivo ACC(ox) activity was also greater in roots of plants grown on high levels of P compared with those grown on low levels, although the influence of VAM infection was partially to counteract the nutritional effect of P on ACC(ox) activity”
Claim · model-written summary
Extracellular peroxidase activity of potato roots increased linearly with increasing abiotic P supply.
- Taxon
- potatoSolanum tuberosume0
- Organ / stage
- rootse1
- Treatment
- increasing abiotic P supplye1
- Gene
- extracellular peroxidasee1
- Outcome
- extracellular peroxidase activity of rootse1
- Direction
- increased linearlye1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“a vesicular-arbuscular mycorrhizal (VAM) fungus and potato (Solanum tuberosum L. cv Russet Burbank) plants”
e1“extracellular peroxidase activity of roots increased linearly with increasing abiotic P supply”
Claim · model-written summary
Raising the abiotic P supply to potato plants at least partially restores the capacity of roots to produce ethylene.
- Taxon
- potatoSolanum tuberosume0
- Treatment
- Raising the abiotic P supplye1
- Outcome
- capacity of roots to produce ethylenee1
- Direction
- partially restorese1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“a vesicular-arbuscular mycorrhizal (VAM) fungus and potato (Solanum tuberosum L. cv Russet Burbank) plants”
e1“Raising the abiotic P supply to plants at least partially restores the capacity of roots to produce ethylene”
Claim · model-written summary
VAM fungi may alter phenolic metabolism of potato roots so as to hinder ethylene production.
- Taxon
- potatoSolanum tuberosume0
- Interactor
- VAM fungie1symbiont
- Outcome
- hinder ethylene productione1
- Qualifier
- may alter phenolic metabolism of rootse1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“a vesicular-arbuscular mycorrhizal (VAM) fungus and potato (Solanum tuberosum L. cv Russet Burbank) plants”
e1“These findings suggest that VAM fungi may alter phenolic metabolism of roots so as to hinder ethylene production and the root's ability to invoke a defense response”
The same questions in other papers
mycorrhiza · physiology: antioxidant enzymes · Solanum tuberosum (potato)Positive and negative results
1 in the opposite direction
- positive
infection · physiology: antioxidant enzymes · Solanum tuberosum (potato)Positive and negative results
7 in the opposite direction
- positive
- positive
- positive
4 papers more in this group
See all 8 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.