Abstract
Inhibition of N 2 fixation under water deficits has been hypothesized to result from N feedback within the plant involving ureides and/or asparagine (Asn). This study was undertaken to investigate ureide and Asn accumulation in shoots and nodules in response to treatments inhibiting nodule activity (acetylene reduction assay, ARA) such as Asn, ureide, or polyethylene glycol application to the nutrient solution of plants, boric acid on leaves, and imposition of a water deficit. ARA inhibition and nodule concentration of Asn and ureide were correlated to the ureide treatment applied (3–15 m M applied in the nutrient solution). Supplying Asn (3–9 m M applied in the nutrient solution) also induced an increase in nodule Asn and ureide concentration, which was associated with ARA inhibition. Spraying boric acid on leaves also inhibited ARA in parallel to an increase in shoot ureide and nodule Asn concentration while nodule ureide remained unchanged. By contrast, polyethylene glycol (PEG) inhibited ARA in parallel to an increase in nodule Asn and ureide concentration while shoot ureide was unchanged. The decline in ARA in response to water deficit was associated with an increase in nodule ureide, Asn and aspartate (Asp), although the increases in Asn and Asp were less than for ureides. Altogether, the results of these experiments indicated that Asn cannot be the only compound involved in the feedback inhibition of ARA. Instead ureide and Asn are probably both involved, either directly by accumulation of products that fail to be exported, or by feedback from the shoot due to an N ‐compound supply that exceeds shoot requirements.
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
Ureide treatment correlated with ARA inhibition and nodule Asn and ureide.
- Taxon
- soybean
Glycine maxt0 - Organ / stage
- nodulee0
- Treatment
- ureide treatment applied (3–15 m M applied in the nutrient solution)e0
- Outcome
- ARA inhibitione0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“ARA inhibition and nodule concentration of Asn and ureide were correlated to the ureide treatment applied (3–15 m M applied in the nutrient solution)”
t0“soybean”
Claim · model-written summary
Applied Asn increased nodule Asn and ureide concentrations.
- Taxon
- soybeanGlycine maxt0
- Treatment
- Asn (3–9 m M applied in the nutrient solution)e0
- Outcome
- nodule Asn and ureide concentratione0
- Direction
- increasee0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Supplying Asn (3–9 m M applied in the nutrient solution) also induced an increase in nodule Asn and ureide concentration”
t0“soybean”
Claim · model-written summary
Applied Asn was associated with ARA inhibition.
- Taxon
- soybeanGlycine maxt0
- Treatment
- Supplying Asne1
- Outcome
- ARA inhibitione0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“which was associated with ARA inhibition”
e1“Supplying Asn (3–9 m M”
t0“soybean”
Claim · model-written summary
Foliar boric acid inhibited ARA.
- Taxon
- soybeanGlycine maxt0
- Treatment
- Spraying boric acid on leavese0
- Outcome
- ARAe0
- Direction
- inhibitede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Spraying boric acid on leaves also inhibited ARA”
t0“soybean”
Claim · model-written summary
Foliar boric acid increased shoot ureide and nodule Asn.
- Taxon
- soybeanGlycine maxt0
- Treatment
- Spraying boric acid on leavese1
- Outcome
- shoot ureide and nodule Asn concentratione0
- Direction
- increasee0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“in parallel to an increase in shoot ureide and nodule Asn concentration”
e1“Spraying boric acid on leaves also inhibited ARA”
t0“soybean”
Claim · model-written summary
Nodule ureide remained unchanged after boric acid.
- Taxon
- soybeanGlycine maxt0
- Treatment
- Spraying boric acid on leavese1
- Outcome
- nodule ureidee0
- Direction
- remained unchangede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“while nodule ureide remained unchanged”
e1“Spraying boric acid on leaves also inhibited ARA”
t0“soybean”
Claim · model-written summary
PEG inhibited ARA.
- Taxon
- soybeanGlycine maxt0
- Treatment
- polyethylene glycol (PEG)e0
- Outcome
- ARAe0
- Direction
- inhibitede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“polyethylene glycol (PEG) inhibited ARA”
t0“soybean”
Claim · model-written summary
PEG increased nodule Asn and ureide.
- Taxon
- soybeanGlycine maxt0
- Treatment
- polyethylene glycol (PEG)e1
- Outcome
- nodule Asn and ureide concentratione0
- Direction
- increasee0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“in parallel to an increase in nodule Asn and ureide concentration”
e1“polyethylene glycol (PEG) inhibited ARA”
t0“soybean”
Claim · model-written summary
Shoot ureide was unchanged with PEG.
- Taxon
- soybeanGlycine maxt0
- Treatment
- polyethylene glycol (PEG)e1
- Outcome
- shoot ureidee0
- Direction
- unchangede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“while shoot ureide was unchanged”
e1“polyethylene glycol (PEG) inhibited ARA”
t0“soybean”
Claim · model-written summary
Water deficit reduced ARA.
- Taxon
- soybeanGlycine maxt0
- Treatment
- water deficite0
- Outcome
- ARAe0
- Direction
- declinee0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The decline in ARA in response to water deficit”
t0“soybean”
Claim · model-written summary
Water deficit increased nodule ureide, Asn and aspartate, with smaller Asn and Asp increases.
- Taxon
- soybeanGlycine maxt0
- Treatment
- water deficite1
- Outcome
- nodule ureide, Asn and aspartate (Asp)e0
- Direction
- increasee0
- Qualifier
- increases in Asn and Asp were less than for ureidese0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“associated with an increase in nodule ureide, Asn and aspartate (Asp), although the increases in Asn and Asp were less than for ureides”
e1“The decline in ARA in response to water deficit”
t0“soybean”
Claim · model-written summary
The authors infer both ureide and Asn may contribute to feedback inhibition of ARA.
- Taxon
- soybeanGlycine maxt0
- Outcome
- feedback from the shoote0
- Qualifier
- ureide and Asn are probably both involvede0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“ureide and Asn are probably both involved, either directly by accumulation of products that fail to be exported, or by feedback from the shoot due to an N ‐compound supply that exceeds shoot requirements”
t0“soybean”
The same questions in other papers
poly(ethylene glycol) · molecular: metabolites · Glycine max (soybean)Positive and negative results
2 papers in the same direction as this paper · 1 in the opposite direction
- no effect
- positive
- negative
drought · symbiosis · Glycine max (soybean)Results differ
38 papers in the same direction as this paper · 2 in the opposite direction
- negative
- negative
- negative
37 papers more in this group
See all 41 papers →application · symbiosis · Glycine max (soybean)Positive and negative results
6 papers in the same direction as this paper · 23 in the opposite direction
- positive
- positive
- positive
26 papers more in this group
See all 30 papers →fertilization · symbiosis · Glycine max (soybean)Positive and negative results
49 papers in the same direction as this paper · 142 in the opposite direction
- positive
- positive
- positive
188 papers more in this group
See all 192 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.