Abstract
When grown in a nutrient solution containing combined nitrogen (NH4NO3), Lotus pedunculatus and L. tenuis seedlings inoculated with a fast-growing strain of Rhizoblum (NZP2037) did neither develop root nodules nor develop flavolans in their roots. In contrast, the roots of nodulated seedlings growing in a nitrogen-free nutrient solution contained flavolans. Flavolan synthesis coincided with root nodule development on these plants. When added as a single dose, high concentrations of NH4NO3 (5 and 10 mg N per plant) stimulated the growth of L. pedunculatus plants but suppressed nodulation and nitrogen fixation. In contrast the continued supply of a low concentration of NH4NO3 (1·0 mg N d−1 per plant) stimulated nitrogen fixation by up to 500%. This large increase in nitrogen fixation was associated with a large increase in nodule fresh weight per plant, a doubling of nodule nitrogenase activity, and a lowering of the flavolan content of the plant roots. The close relationship between nitrogen deficiency, nodule development, and flavolan synthesis in L. pedunculatus meant that it was not possible (by nitrogen pretreatment of plants) to alter the ineffective nodule response of a Rhizobium strain (NZP2213) sensitive to the flavolan present in the roots of this plant.
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Claims 12
Claim · model-written summary
Combined nitrogen prevented root nodules in inoculated Lotus seedlings.
- Taxon
- Lotus pedunculatus
Lotus pedunculatuse0 - Treatment
- combined nitrogen (NH4NO3)e0
- Interactor
- Rhizoblum (NZP2037)e0symbiont
- Outcome
- root nodulese0
Not reportedComparatorDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“When grown in a nutrient solution containing combined nitrogen (NH4NO3), Lotus pedunculatus and L. tenuis seedlings inoculated with a fast-growing strain of Rhizoblum (NZP2037) did neither develop root nodules nor develop flavolans in their roots.”
Claim · model-written summary
Combined nitrogen prevented root flavolans in inoculated Lotus seedlings.
- Taxon
- L. tenuis
Lotus tenuise0 - Treatment
- combined nitrogen (NH4NO3)e0
- Interactor
- Rhizoblum (NZP2037)e0symbiont
- Outcome
- flavolans in their rootse0
Not reportedComparatorDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“When grown in a nutrient solution containing combined nitrogen (NH4NO3), Lotus pedunculatus and L. tenuis seedlings inoculated with a fast-growing strain of Rhizoblum (NZP2037) did neither develop root nodules nor develop flavolans in their roots.”
Claim · model-written summary
Nodulated seedlings in nitrogen-free solution had root flavolans.
- Taxon
- Lotus pedunculatusLotus pedunculatuse1
- Outcome
- contained flavolanse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the roots of nodulated seedlings growing in a nitrogen-free nutrient solution contained flavolans.”
e1“Lotus pedunculatus and L. tenuis seedlings”
t0“Effectiveness ofLotusRoot Nodules”
Claim · model-written summary
Flavolan synthesis coincided with nodule development.
- Taxon
- Lotus pedunculatusLotus pedunculatuse1
- Organ / stage
- root nodulee0
- Outcome
- Flavolan synthesise0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Flavolan synthesis coincided with root nodule development on these plants.”
e1“Lotus pedunculatus and L. tenuis seedlings”
t0“Effectiveness ofLotusRoot Nodules”
Claim · model-written summary
High single doses of NH4NO3 stimulated Lotus pedunculatus growth.
- Taxon
- L. pedunculatusLotus pedunculatuse0
- Treatment
- NH4NO3 (5 and 10 mg N per plant)e0
- Outcome
- growthe0
- Direction
- stimulatede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“When added as a single dose, high concentrations of NH4NO3 (5 and 10 mg N per plant) stimulated the growth of L. pedunculatus plants but suppressed nodulation and nitrogen fixation.”
Claim · model-written summary
High single doses of NH4NO3 suppressed nodulation.
- Taxon
- L. pedunculatusLotus pedunculatuse0
- Treatment
- NH4NO3 (5 and 10 mg N per plant)e0
- Outcome
- nodulatione0
- Direction
- suppressede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“When added as a single dose, high concentrations of NH4NO3 (5 and 10 mg N per plant) stimulated the growth of L. pedunculatus plants but suppressed nodulation and nitrogen fixation.”
Claim · model-written summary
High single doses of NH4NO3 suppressed nitrogen fixation.
- Taxon
- L. pedunculatusLotus pedunculatuse0
- Treatment
- NH4NO3 (5 and 10 mg N per plant)e0
- Outcome
- nitrogen fixatione0
- Direction
- suppressede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“When added as a single dose, high concentrations of NH4NO3 (5 and 10 mg N per plant) stimulated the growth of L. pedunculatus plants but suppressed nodulation and nitrogen fixation.”
Claim · model-written summary
Continued low-dose NH4NO3 increased nitrogen fixation by up to 500%.
- Taxon
- L. pedunculatusLotus pedunculatuse1
- Treatment
- NH4NO3 (1·0 mg N d−1 per plant)e0
- Outcome
- nitrogen fixatione0
- Direction
- stimulatede0
- Value
- 500%e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the continued supply of a low concentration of NH4NO3 (1·0 mg N d−1 per plant) stimulated nitrogen fixation by up to 500%.”
e1“L. pedunculatus plants”
t0“Effectiveness ofLotusRoot Nodules”
Claim · model-written summary
Higher fixation accompanied increased nodule fresh weight.
- Taxon
- L. pedunculatusLotus pedunculatuse1
- Organ / stage
- nodulee0
- Outcome
- nodule fresh weight per plante0
- Direction
- increasee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“This large increase in nitrogen fixation was associated with a large increase in nodule fresh weight per plant, a doubling of nodule nitrogenase activity, and a lowering of the flavolan content of the plant roots.”
e1“L. pedunculatus plants”
t0“Effectiveness ofLotusRoot Nodules”
Claim · model-written summary
Higher fixation accompanied doubled nitrogenase activity.
- Taxon
- L. pedunculatusLotus pedunculatuse1
- Organ / stage
- nodulee0
- Outcome
- nodule nitrogenase activitye0
- Direction
- doublinge0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“This large increase in nitrogen fixation was associated with a large increase in nodule fresh weight per plant, a doubling of nodule nitrogenase activity, and a lowering of the flavolan content of the plant roots.”
e1“L. pedunculatus plants”
t0“Effectiveness ofLotusRoot Nodules”
Claim · model-written summary
Higher fixation accompanied lower root flavolan content.
- Taxon
- L. pedunculatusLotus pedunculatuse1
- Organ / stage
- plant rootse0
- Outcome
- flavolan content of the plant rootse0
- Direction
- loweringe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“This large increase in nitrogen fixation was associated with a large increase in nodule fresh weight per plant, a doubling of nodule nitrogenase activity, and a lowering of the flavolan content of the plant roots.”
e1“L. pedunculatus plants”
t0“Effectiveness ofLotusRoot Nodules”
Claim · model-written summary
Nitrogen pretreatment could not change the ineffective NZP2213 nodule response.
- Taxon
- L. pedunculatusLotus pedunculatuse1
- Treatment
- nitrogen pretreatment of plantse0
- Interactor
- Rhizobium strain (NZP2213)e0symbiont
- Outcome
- ineffective nodule responsee0
- Direction
- not possiblee0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“it was not possible (by nitrogen pretreatment of plants) to alter the ineffective nodule response of a Rhizobium strain (NZP2213) sensitive to the flavolan present in the roots of this plant.”
e1“L. pedunculatus plants”
t0“Effectiveness ofLotusRoot Nodules”
The same questions in other papers
nitrogen · symbiosis · Lotus pedunculatusResults agree
1 paper in the same direction as this paper
- negative
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.