Abstract
Abstract Experiments were conducted in growth chambers of the Phytotron to evaluate the effects of humic and fulvic acids on growth and ion uptake by tobacco plants grown to flowering. When small amounts of humic or fulvic acids were added to media used to grow seedlings, the dry weight of roots and tops and the height of the plants subsequently grown in a nutrient solution with small amounts of humic or fulvic acids increased, while at high rates of humic acids they decreased. Generally, there was a trend for low rates of humic acids to increase concentration of Ca and Mg in roots and leaves and to decrease Fe concentration in roots. The total content of N, K, P, Ca, Mg and Fe in the stalk and leaves increased in the presence of small amounts of humic or fulvic acids in the nutrient solution. Low rates of humic or fulvic acids in the growth medium facilitated the adsorption of Ca, Mg and Fe and their translocation within the plant. For high rates of humic acids there was a trend to decrease the total content of N, K, P, Ca and Fe in the roots and leaves of the plant.
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Claims 7
Claim · model-written summary
Small amounts of humic or fulvic acids increased root and top dry weight and plant height.
- Taxon
- tobacco
Nicotiana tabacumt0 - Treatment
- small amounts of humic or fulvic acidse0
- Outcome
- dry weight of roots and tops and the height of the plantse0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“When small amounts of humic or fulvic acids were added to media used to grow seedlings, the dry weight of roots and tops and the height of the plants subsequently grown in a nutrient solution with small amounts of humic or fulvic acids increased”
t0“tobacco”
Claim · model-written summary
High humic acid rates decreased root and top dry weight and plant height.
- Taxon
- tobaccoNicotiana tabacumt0
- Treatment
- high rates of humic acidse0
- Outcome
- dry weight of roots and tops and the height of the plantse1
- Direction
- decreasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“while at high rates of humic acids they decreased”
t0“tobacco”
e1“the dry weight of roots and tops and the height of the plants subsequently grown in a nutrient solution with small amounts of humic or fulvic acids increased”
Claim · model-written summary
Low humic acid rates tended to increase root and leaf Ca and Mg concentrations.
- Taxon
- tobaccoNicotiana tabacumt0
- Treatment
- low rates of humic acidse0
- Outcome
- concentration of Ca and Mg in roots and leavese0
- Direction
- increasee0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“low rates of humic acids to increase concentration of Ca and Mg in roots and leaves”
t0“tobacco”
Claim · model-written summary
Low humic acid rates tended to decrease root Fe concentration.
- Taxon
- tobaccoNicotiana tabacumt0
- Treatment
- low rates of humic acidse1
- Outcome
- Fe concentration in rootse0
- Direction
- decreasee0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“to decrease Fe concentration in roots”
e1“low rates of humic acids to increase concentration of Ca and Mg in roots and leaves”
t0“tobacco”
Claim · model-written summary
Small amounts of humic or fulvic acids increased total N, K and P content in stalks and leaves.
- Taxon
- tobaccoNicotiana tabacumt0
- Treatment
- small amounts of humic or fulvic acidse0
- Outcome
- total content of N, K, P, Ca, Mg and Fe in the stalk and leavese0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The total content of N, K, P, Ca, Mg and Fe in the stalk and leaves increased in the presence of small amounts of humic or fulvic acids in the nutrient solution”
t0“tobacco”
Claim · model-written summary
Low humic or fulvic acid rates facilitated Ca, Mg and Fe adsorption and translocation.
- Taxon
- tobaccoNicotiana tabacumt0
- Treatment
- Low rates of humic or fulvic acidse0
- Outcome
- adsorption of Ca, Mg and Fe and their translocatione0
- Direction
- facilitatede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Low rates of humic or fulvic acids in the growth medium facilitated the adsorption of Ca, Mg and Fe and their translocation within the plant”
t0“tobacco”
Claim · model-written summary
High humic acid rates tended to decrease total N, K, P, Ca and Fe in roots and leaves.
- Taxon
- tobaccoNicotiana tabacumt0
- Treatment
- high rates of humic acidse0
- Outcome
- total content of N, K, P, Ca and Fe in the roots and leavese0
- Direction
- decreasee0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“For high rates of humic acids there was a trend to decrease the total content of N, K, P, Ca and Fe in the roots and leaves of the plant”
t0“tobacco”
The same questions in other papers
other · growth · Nicotiana tabacum (tobacco)Results differ
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- no effect
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See all 20 papers →other · molecular: metabolites · Nicotiana tabacum (tobacco)Results agree
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See all 9 papers →other · nutrient: content · Nicotiana tabacum (tobacco)Results agree
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- positive
- positive
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See all 17 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.