Abstract
Effects of pH, calcium (Ca), and aluminium (Al) on the growth and nodulation of cowpea (Vigna unguiculata) were studied in large-volume, dilute nutrient solutions. Ca concentrations over the range 0.05 mM to 2.5 mM, and pH over the range 4.5 to 5.5, had no significant effect on the growth of the host plant. However, the combination of low pH and low Ca delayed nodulation and strongly depressed nodule number and nodule dry weight. At the highest Ca concentration, effects of pH on nodule number were small and not significant, and effects on nodule weight, although significant, were much smaller than at the lowest Ca concentration. It was concluded that nodulation was more sensitive to low Ca and low pH than was host plant growth. At pH 4.5 and 0.5 mM Ca, A1 delayed and depressed nodulation. An activity of 12.7 8M Al delayed nodulation by four days, and reduced nodule number and nodule dry weight drastically. At higher Al activities, nodulation was reduced to zero. The critical Al activities (10% reduction) were approx. 0.3 and 0.5 ,8M for nodule number and nodule dry weight. The dry weight of tops and roots showed a roughly linear decrease with increasing Al activity over the range 0 to 8 8M, both in inoculated plants supplied with 'starter nitrogen' and in plants supplied continuously with adequate mineral nitrogen. Critical A1 activities for growth were in the range of 4 to 8 PM. It was concluded that nodulation was much more sensitive to Al than was host plant growth. The results are discussed in relation to recent literature on the acid tolerance of cowpea.
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Claims 13
Claim · model-written summary
Calcium from 0.05 to 2.5 mM and pH from 4.5 to 5.5 had no significant effect on cowpea growth.
- Taxon
- cowpea
Vigna unguiculatat0 - Treatment
- Ca concentrations over the range 0.05 mM to 2.5 mM, and pH over the range 4.5 to 5.5e0
- Outcome
- growth of the host plante0
- Direction
- no significant effecte0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Ca concentrations over the range 0.05 mM to 2.5 mM, and pH over the range 4.5 to 5.5, had no significant effect on the growth of the host plant.”
t0“Effect of solution pH, external calcium concentration, and aluminium activity on nodulation and early growth of cowpea”
Claim · model-written summary
Combined low pH and low calcium delayed cowpea nodulation.
- Taxon
- cowpeaVigna unguiculatat0
- Treatment
- combination of low pH and low Cae0
- Outcome
- nodulatione0
- Direction
- delayede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the combination of low pH and low Ca delayed nodulation”
t0“Effect of solution pH, external calcium concentration, and aluminium activity on nodulation and early growth of cowpea”
Claim · model-written summary
Combined low pH and low calcium strongly reduced nodule number and dry weight.
- Taxon
- cowpeaVigna unguiculatat0
- Treatment
- combination of low pH and low Cae0
- Outcome
- nodule number and nodule dry weighte0
- Direction
- depressede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the combination of low pH and low Ca delayed nodulation and strongly depressed nodule number and nodule dry weight”
t0“Effect of solution pH, external calcium concentration, and aluminium activity on nodulation and early growth of cowpea”
Claim · model-written summary
At the highest calcium concentration, pH effects on nodule number were small and nonsignificant.
- Taxon
- cowpeaVigna unguiculatat0
- Treatment
- pHe0
- Outcome
- nodule numbere0
- Direction
- smalle0
- Qualifier
- highest Ca concentratione0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“At the highest Ca concentration, effects of pH on nodule number were small and not significant”
t0“Effect of solution pH, external calcium concentration, and aluminium activity on nodulation and early growth of cowpea”
Claim · model-written summary
At the highest calcium concentration, pH effects on nodule weight remained significant but were much smaller than at the lowest calcium concentration.
- Taxon
- cowpeaVigna unguiculatat0
- Treatment
- highest Ca concentratione0
- Outcome
- nodule weighte0
- Direction
- smallere0
- Comparator
- lowest Ca concentratione0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“At the highest Ca concentration, effects of pH on nodule number were small and not significant, and effects on nodule weight, although significant, were much smaller than at the lowest Ca concentration.”
t0“Effect of solution pH, external calcium concentration, and aluminium activity on nodulation and early growth of cowpea”
Claim · model-written summary
At pH 4.5 and 0.5 mM calcium, aluminium delayed nodulation.
- Taxon
- cowpeaVigna unguiculatat0
- Treatment
- A1e0
- Outcome
- nodulatione0
- Direction
- delayede0
- Qualifier
- pH 4.5 and 0.5 mM Cae0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“At pH 4.5 and 0.5 mM Ca, A1 delayed and depressed nodulation.”
t0“Effect of solution pH, external calcium concentration, and aluminium activity on nodulation and early growth of cowpea”
Claim · model-written summary
Aluminium activity of 12.7 8M delayed nodulation by four days.
- Taxon
- cowpeaVigna unguiculatat0
- Treatment
- 12.7 8M Ale0
- Outcome
- nodulatione0
- Direction
- delayede0
- Value
- four dayse0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“An activity of 12.7 8M Al delayed nodulation by four days”
t0“Effect of solution pH, external calcium concentration, and aluminium activity on nodulation and early growth of cowpea”
Claim · model-written summary
Aluminium activity of 12.7 8M drastically reduced nodule number and nodule dry weight.
- Taxon
- cowpeaVigna unguiculatat0
- Treatment
- 12.7 8M Ale0
- Outcome
- nodule number and nodule dry weighte0
- Direction
- reducede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“An activity of 12.7 8M Al delayed nodulation by four days, and reduced nodule number and nodule dry weight drastically.”
t0“Effect of solution pH, external calcium concentration, and aluminium activity on nodulation and early growth of cowpea”
Claim · model-written summary
Higher aluminium activities reduced nodulation to zero.
- Taxon
- cowpeaVigna unguiculatat0
- Treatment
- higher Al activitiese0
- Outcome
- nodulatione0
- Direction
- reducede0
- Value
- zeroe0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“At higher Al activities, nodulation was reduced to zero.”
t0“Effect of solution pH, external calcium concentration, and aluminium activity on nodulation and early growth of cowpea”
Claim · model-written summary
The critical aluminium activity for 10% reduction of nodule number was approximately 0.3 ,8M.
- Taxon
- cowpeaVigna unguiculatat0
- Outcome
- nodule numbere0
- Direction
- reductione0
- Value
- 10%e0
- Qualifier
- approx. 0.3 and 0.5 ,8Me0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The critical Al activities (10% reduction) were approx. 0.3 and 0.5 ,8M for nodule number and nodule dry weight.”
t0“Effect of solution pH, external calcium concentration, and aluminium activity on nodulation and early growth of cowpea”
Claim · model-written summary
The critical aluminium activity for 10% reduction of nodule dry weight was approximately 0.5 ,8M.
- Taxon
- cowpeaVigna unguiculatat0
- Outcome
- nodule dry weighte0
- Direction
- reductione0
- Value
- 10%e0
- Qualifier
- approx. 0.3 and 0.5 ,8Me0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The critical Al activities (10% reduction) were approx. 0.3 and 0.5 ,8M for nodule number and nodule dry weight.”
t0“Effect of solution pH, external calcium concentration, and aluminium activity on nodulation and early growth of cowpea”
Claim · model-written summary
Top and root dry weight decreased roughly linearly with aluminium activity from 0 to 8 8M under both nitrogen regimes.
- Taxon
- cowpeaVigna unguiculatat0
- Treatment
- increasing Al activity over the range 0 to 8 8Me0
- Outcome
- dry weight of tops and rootse0
- Direction
- decreasee0
- Qualifier
- both in inoculated plants supplied with 'starter nitrogen' and in plants supplied continuously with adequate mineral nitrogene0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The dry weight of tops and roots showed a roughly linear decrease with increasing Al activity over the range 0 to 8 8M, both in inoculated plants supplied with 'starter nitrogen' and in plants supplied continuously with adequate mineral nitrogen.”
t0“Effect of solution pH, external calcium concentration, and aluminium activity on nodulation and early growth of cowpea”
Claim · model-written summary
Critical aluminium activities for cowpea growth were in the range 4 to 8 PM.
- Taxon
- cowpeaVigna unguiculatat0
- Outcome
- growthe0
- Value
- 4 to 8 PMe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Critical A1 activities for growth were in the range of 4 to 8 PM.”
t0“Effect of solution pH, external calcium concentration, and aluminium activity on nodulation and early growth of cowpea”
The same questions in other papers
calcium atom · growth · Vigna unguiculata (cowpea)Positive and negative results
1 paper in the same direction as this paper · 2 in the opposite direction
- positive
- positive
- no effect
aluminium atom · symbiosis · Vigna unguiculata (cowpea)Results agree
1 paper in the same direction as this paper
- negative
ph · symbiosis · Vigna unguiculata (cowpea)Results agree
1 paper in the same direction as this paper
- negative
ph · growth · Vigna unguiculata (cowpea)Results agree
3 papers in the same direction as this paper
- negative
- no effect
- 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.