Abstract
Abstract The calcium ionophore A23187 was used to separate the processes of infection and nodule development from nitrogen fixation in soybeans. Seedlings of Glycine max (L.) Merr. cv. Williams were grown in solution cultures containing three concentrations of Ca 2+ (0.1, 0.5 or 1.0 m M ) with or without 0.5 μ M ionophore A23187. Three weeks after inoculation with Rhizobium japonicum , strain B1. plants were harvested. Low Ca 2+ (0.1 m M ) significantly reduced nodule number and weight, acetylene reduction, fresh weight of roots and shoots and increased lengths of 2nd and 3rd internodes. There were no significant differences between 0.5 and 1.0 m M Ca 2 in their influence on any parameters measured, except for Ca 2+ concentration in the tissue. The ionophore A23187 significantly reduced nodule number and weight, and increased internode lengths, but it had no effect on acetylene reduction or fresh weight of roots and tops. The ionophore did not affect the Ca 2+ concentration of roots, tops or nodules. Therefore, nitrogen fixation rate is partially independent of number and weight of nodules. The single most important result of this study is that the ionophore A23187 affected critical steps in the infection process or nodule development without influencing subsequent nitrogen fixation.
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Claims 12
Claim · model-written summary
Low calcium reduced nodule number and weight
- Taxon
- Soybeans
Glycine maxt0 - Treatment
- Low Ca 2+ (0.1 m M )e0
- Outcome
- nodule number and weighte0
- Direction
- reducede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Low Ca 2+ (0.1 m M ) significantly reduced nodule number and weight, acetylene reduction, fresh weight of roots and shoots and increased lengths of 2nd and 3rd internodes.”
t0“Soybeans”
Claim · model-written summary
Low calcium reduced acetylene reduction
- Taxon
- SoybeansGlycine maxt0
- Treatment
- Low Ca 2+ (0.1 m M )e0
- Outcome
- acetylene reductione0
- Direction
- reducede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Low Ca 2+ (0.1 m M ) significantly reduced nodule number and weight, acetylene reduction, fresh weight of roots and shoots and increased lengths of 2nd and 3rd internodes.”
t0“Soybeans”
Claim · model-written summary
Low calcium reduced fresh weight of roots and shoots
- Taxon
- SoybeansGlycine maxt0
- Treatment
- Low Ca 2+ (0.1 m M )e0
- Outcome
- fresh weight of roots and shootse0
- Direction
- reducede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Low Ca 2+ (0.1 m M ) significantly reduced nodule number and weight, acetylene reduction, fresh weight of roots and shoots and increased lengths of 2nd and 3rd internodes.”
t0“Soybeans”
Claim · model-written summary
Low calcium increased lengths of 2nd and 3rd internodes
- Taxon
- SoybeansGlycine maxt0
- Treatment
- Low Ca 2+ (0.1 m M )e0
- Outcome
- lengths of 2nd and 3rd internodese0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Low Ca 2+ (0.1 m M ) significantly reduced nodule number and weight, acetylene reduction, fresh weight of roots and shoots and increased lengths of 2nd and 3rd internodes.”
t0“Soybeans”
Claim · model-written summary
Most measured parameters did not differ between 0.5 and 1.0 mM calcium
- Taxon
- SoybeansGlycine maxt0
- Outcome
- any parameters measurede0
- Direction
- no significant differencese0
- Qualifier
- except for Ca 2+ concentration in the tissuee0
- Comparator
- 0.5 and 1.0 m M Ca 2e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“There were no significant differences between 0.5 and 1.0 m M Ca 2 in their influence on any parameters measured, except for Ca 2+ concentration in the tissue.”
t0“Soybeans”
Claim · model-written summary
Ionophore A23187 reduced nodule number and weight
- Taxon
- SoybeansGlycine maxt0
- Treatment
- ionophore A23187e0
- Outcome
- nodule number and weighte0
- Direction
- reducede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The ionophore A23187 significantly reduced nodule number and weight, and increased internode lengths, but it had no effect on acetylene reduction or fresh weight of roots and tops.”
t0“Soybeans”
Claim · model-written summary
Ionophore A23187 increased internode lengths
- Taxon
- SoybeansGlycine maxt0
- Treatment
- ionophore A23187e0
- Outcome
- internode lengthse0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The ionophore A23187 significantly reduced nodule number and weight, and increased internode lengths, but it had no effect on acetylene reduction or fresh weight of roots and tops.”
t0“Soybeans”
Claim · model-written summary
Ionophore A23187 no effect acetylene reduction
- Taxon
- SoybeansGlycine maxt0
- Treatment
- ionophore A23187e0
- Outcome
- acetylene reductione0
- Direction
- no effecte0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The ionophore A23187 significantly reduced nodule number and weight, and increased internode lengths, but it had no effect on acetylene reduction or fresh weight of roots and tops.”
t0“Soybeans”
Claim · model-written summary
Ionophore A23187 no effect fresh weight of roots and tops
- Taxon
- SoybeansGlycine maxt0
- Treatment
- ionophore A23187e0
- Outcome
- fresh weight of roots and topse0
- Direction
- no effecte0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The ionophore A23187 significantly reduced nodule number and weight, and increased internode lengths, but it had no effect on acetylene reduction or fresh weight of roots and tops.”
t0“Soybeans”
Claim · model-written summary
Ionophore did not affect calcium concentrations
- Taxon
- SoybeansGlycine maxt0
- Treatment
- ionophoree0
- Outcome
- Ca 2+ concentration of roots, tops or nodulese0
- Direction
- did not affecte0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The ionophore did not affect the Ca 2+ concentration of roots, tops or nodules.”
t0“Soybeans”
Claim · model-written summary
Fixation rate was partly independent of nodule number and weight
- Taxon
- SoybeansGlycine maxt0
- Organ / stage
- nodulese0
- Outcome
- nitrogen fixation ratee0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Therefore, nitrogen fixation rate is partially independent of number and weight of nodules.”
t0“Soybeans”
Claim · model-written summary
Ionophore affected infection or nodulation without affecting fixation
- Taxon
- SoybeansGlycine maxt0
- Treatment
- ionophore A23187e0
- Outcome
- infection process or nodule developmente0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The single most important result of this study is that the ionophore A23187 affected critical steps in the infection process or nodule development without influencing subsequent nitrogen fixation.”
t0“Soybeans”
The same questions in other papers
calcium(2+) · growth · Glycine max (soybean)Positive and negative results
3 in the opposite direction
- positive
- positive
- positive
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.