Abstract
The absorption and translocation of boron by sunflower plants (Helianthus annuus L.) grown under controlled-environment conditions were investigated. Exudates in a 43-hr period from the cut stem ends of the root systems of detopped plants contained the same amount of boron whether the roots were immersed in nutrient solutions containing 500 μg or 1,000 μg of boron per liter. Plants given a total of 60 μg of boron in the substrate, but in varied amounts and times of application, showed no differences among the treatments in the accumulation of boron by their mature leaves. Two of the four series with multiple application, however, showed delays in the onset of severe symptoms of boron deficiency as compared with the series with an initial single 60-μg application. Significant lateral transport of boron occurred at the stem tip and in leaf blades when boron was supplied to only half of a split root system at 500 or 1,000 μg per root-half. Slight, though not significant, lateral transport occurred across the lower levels of the stems in these series. Lateral transport of boron at the lower internodes was demonstrated when boron was supplied to only one-half of the root system in higher quantities (5,000 or 10,000 μg per root half). Little or no lateral transport in leaves or stems was observed with boron application of 50 or 100 μg per root-half. Although mature leaves sprayed with 10-ppm boron solution (as boric acid) showed an increase in dialyzable boron content, this soluble boron was not translocated from the leaves. No differences in growth were evident between plants receiving dialyzable boron extracted from leaf tissues and those receiving boric acid in the nutrient solutions. Non-dialyzable boron in the non-particulate fraction of leaf homogenate, however, was not utilized by plants when it was added to the nutrient solution. Reversing the transpiration stream of a leaf by placing it in a dilute minus-boron nutrient solution and withholding a water supply from other organs of the plant did not result in a movement of boron from the leaf to the apical meristem. Some of the boron in the leaf, however, was readily leached into the nutrient solution. Covering the top surface of a leaf with aluminum foil to limit photosynthesis did not result in a change in its boron content. A nitrogen-deficient nutrient solution adversely affected the capacity of plants to accumulate boron. From the results of the experiments described, it is concluded that one of the prime factors controlling the distribution of boron in sunflower plants is the extent and location of the metabolic requirement for this element. It is further proposed that immobility of boron in the leaves of this species results from some type of translocation block in the vascular tissue and not from a fixation of boron in a soluble but non-utilizable form.
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Claims 17
Claim · model-written summary
Exudates from detopped sunflower plants contained the same amount of boron whether roots were immersed in 500 or 1,000 μg per liter nutrient solutions.
- Taxon
- sunflower plants
Helianthus annuuse0 - Organ / stage
- cut stem endse1
- Treatment
- nutrient solutions containing 500 μge1
- Outcome
- amount of borone1
- Direction
- the samee1
- Qualifier
- 43-hr periode1
- Comparator
- 1,000 μg of boron per litere1
- Setting
- controlled-environment conditionse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“boron by sunflower plants (Helianthus annuus L.) grown under controlled-environment conditions”
e1“Exudates in a 43-hr period from the cut stem ends of the root systems of detopped plants contained the same amount of boron whether the roots were immersed in nutrient solutions containing 500 μg or 1,000 μg of boron per liter”
Claim · model-written summary
Plants given a total of 60 μg boron in varied amounts and times of application showed no differences among treatments in boron accumulation in mature leaves.
- Taxon
- sunflower plantsHelianthus annuuse0
- Treatment
- varied amounts and times of applicatione2
- Outcome
- accumulation of boron by their mature leavese2
- Direction
- no differencese2
- Comparator
- among the treatmentse2
- Setting
- controlled-environment conditionse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“boron by sunflower plants (Helianthus annuus L.) grown under controlled-environment conditions”
e2“Plants given a total of 60 μg of boron in the substrate, but in varied amounts and times of application, showed no differences among the treatments in the accumulation of boron by their mature leaves”
Claim · model-written summary
Two of four multiple-application series delayed the onset of severe boron deficiency symptoms compared with a single initial 60-μg application.
- Taxon
- sunflower plantsHelianthus annuuse0
- Treatment
- multiple applicatione3
- Outcome
- onset of severe symptoms of boron deficiencye3
- Direction
- delayse3
- Comparator
- an initial single 60-μg applicatione3
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“boron by sunflower plants (Helianthus annuus L.) grown under controlled-environment conditions”
e3“Two of the four series with multiple application, however, showed delays in the onset of severe symptoms of boron deficiency as compared with the series with an initial single 60-μg application”
Claim · model-written summary
Significant lateral transport of boron occurred at the stem tip and in leaf blades when boron was supplied to one half of a split root system at 500 or 1,000 μg per root-half.
- Taxon
- sunflower plantsHelianthus annuuse0
- Organ / stage
- stem tip and in leaf bladese4
- Treatment
- boron was supplied to only half of a split root system at 500 or 1,000 μg per root-halfe4
- Outcome
- lateral transport of borone4
Not reportedComparatorDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“boron by sunflower plants (Helianthus annuus L.) grown under controlled-environment conditions”
e4“Significant lateral transport of boron occurred at the stem tip and in leaf blades when boron was supplied to only half of a split root system at 500 or 1,000 μg per root-half”
Claim · model-written summary
Slight, non-significant lateral transport of boron occurred across the lower stem levels in the split-root series.
- Taxon
- sunflower plantsHelianthus annuuse0
- Organ / stage
- lower levels of the stemse5
- Treatment
- boron was supplied to only half of a split root system at 500 or 1,000 μg per root-halfe4
- Outcome
- lateral transporte5
Not reportedComparatorDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“boron by sunflower plants (Helianthus annuus L.) grown under controlled-environment conditions”
e4“Significant lateral transport of boron occurred at the stem tip and in leaf blades when boron was supplied to only half of a split root system at 500 or 1,000 μg per root-half”
e5“Slight, though not significant, lateral transport occurred across the lower levels of the stems in these series”
Claim · model-written summary
Lateral transport of boron at the lower internodes was demonstrated when boron was supplied to one half of the root system at 5,000 or 10,000 μg per root half.
- Taxon
- sunflower plantsHelianthus annuuse0
- Organ / stage
- lower internodese6
- Treatment
- boron was supplied to only one-half of the root system in higher quantities (5,000 or 10,000 μg per root half)e6
- Outcome
- Lateral transport of borone6
Not reportedComparatorDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“boron by sunflower plants (Helianthus annuus L.) grown under controlled-environment conditions”
e6“Lateral transport of boron at the lower internodes was demonstrated when boron was supplied to only one-half of the root system in higher quantities (5,000 or 10,000 μg per root half)”
Claim · model-written summary
Little or no lateral transport of boron occurred in leaves or stems with boron application of 50 or 100 μg per root-half.
- Taxon
- sunflower plantsHelianthus annuuse0
- Treatment
- boron application of 50 or 100 μg per root-halfe7
- Outcome
- lateral transport in leaves or stemse7
- Direction
- Little or noe7
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“boron by sunflower plants (Helianthus annuus L.) grown under controlled-environment conditions”
e7“Little or no lateral transport in leaves or stems was observed with boron application of 50 or 100 μg per root-half”
Claim · model-written summary
Mature leaves sprayed with 10-ppm boric acid solution showed an increase in dialyzable boron content.
- Taxon
- sunflower plantsHelianthus annuuse0
- Treatment
- mature leaves sprayed with 10-ppm boron solution (as boric acid)e6
- Outcome
- dialyzable boron contente6
- Direction
- increasee6
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“boron by sunflower plants (Helianthus annuus L.) grown under controlled-environment conditions”
e6“mature leaves sprayed with 10-ppm boron solution (as boric acid) showed an increase in dialyzable boron content”
Claim · model-written summary
The soluble boron applied by spraying was not translocated from the leaves.
- Taxon
- sunflower plantsHelianthus annuuse0
- Treatment
- mature leaves sprayed with 10-ppm boron solution (as boric acid)e6
- Outcome
- translocated from the leavese5
Not reportedComparatorDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“boron by sunflower plants (Helianthus annuus L.) grown under controlled-environment conditions”
e6“mature leaves sprayed with 10-ppm boron solution (as boric acid) showed an increase in dialyzable boron content”
e5“this soluble boron was not translocated from the leaves”
Claim · model-written summary
No growth differences were evident between plants receiving leaf-extracted dialyzable boron and plants receiving boric acid in the nutrient solution.
- Taxon
- sunflower plantsHelianthus annuuse0
- Treatment
- dialyzable boron extracted from leaf tissuese1
- Outcome
- growthe1
- Direction
- No differencese1
- Comparator
- boric acid in the nutrient solutionse1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“boron by sunflower plants (Helianthus annuus L.) grown under controlled-environment conditions”
e1“No differences in growth were evident between plants receiving dialyzable boron extracted from leaf tissues and those receiving boric acid in the nutrient solutions”
Claim · model-written summary
Non-dialyzable boron in the non-particulate fraction of leaf homogenate was not utilized by plants when added to the nutrient solution.
- Taxon
- sunflower plantsHelianthus annuuse0
- Treatment
- Non-dialyzable boron in the non-particulate fraction of leaf homogenatee1
- Outcome
- utilized by plantse1
- Direction
- not utilizede1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“boron by sunflower plants (Helianthus annuus L.) grown under controlled-environment conditions”
e1“Non-dialyzable boron in the non-particulate fraction of leaf homogenate, however, was not utilized by plants when it was added to the nutrient solution”
Claim · model-written summary
Reversing the transpiration stream of a leaf did not move boron from the leaf to the apical meristem.
- Taxon
- sunflower plantsHelianthus annuuse0
- Organ / stage
- apical meristeme1
- Treatment
- Reversing the transpiration stream of a leaf by placing it in a dilute minus-boron nutrient solution and withholding a water supply from other organs of the plante1
- Outcome
- movement of boron from the leaf to the apical meristeme1
- Direction
- did not result ine1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“boron by sunflower plants (Helianthus annuus L.) grown under controlled-environment conditions”
e1“Reversing the transpiration stream of a leaf by placing it in a dilute minus-boron nutrient solution and withholding a water supply from other organs of the plant did not result in a movement of boron from the leaf to the apical meristem”
Claim · model-written summary
Some boron in the leaf was readily leached into the nutrient solution.
- Taxon
- sunflower plantsHelianthus annuuse0
- Organ / stage
- the leafe1
- Outcome
- readily leached into the nutrient solutione1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“boron by sunflower plants (Helianthus annuus L.) grown under controlled-environment conditions”
e1“Some of the boron in the leaf, however, was readily leached into the nutrient solution”
Claim · model-written summary
Covering a leaf's top surface with aluminum foil to limit photosynthesis did not change its boron content.
- Taxon
- sunflower plantsHelianthus annuuse0
- Treatment
- Covering the top surface of a leaf with aluminum foil to limit photosynthesise1
- Outcome
- boron contente1
- Direction
- did not result in a changee1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“boron by sunflower plants (Helianthus annuus L.) grown under controlled-environment conditions”
e1“Covering the top surface of a leaf with aluminum foil to limit photosynthesis did not result in a change in its boron content”
Claim · model-written summary
A nitrogen-deficient nutrient solution adversely decreased the capacity of plants to accumulate boron.
- Taxon
- sunflower plantsHelianthus annuuse0
- Treatment
- A nitrogen-deficient nutrient solutione1
- Outcome
- the capacity of plants to accumulate borone1
- Direction
- decreaseinferrede1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“boron by sunflower plants (Helianthus annuus L.) grown under controlled-environment conditions”
e1“A nitrogen-deficient nutrient solution adversely affected the capacity of plants to accumulate boron”
Claim · model-written summary
The extent and location of the metabolic requirement for boron is one of the prime factors controlling boron distribution in sunflower plants.
- Taxon
- sunflower plantsHelianthus annuuse1
- Outcome
- distribution of borone1
- Qualifier
- the extent and location of the metabolic requirement for this elemente1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“it is concluded that one of the prime factors controlling the distribution of boron in sunflower plants is the extent and location of the metabolic requirement for this element”
Claim · model-written summary
Boron immobility in sunflower leaves is proposed to result from a translocation block in the vascular tissue rather than from fixation in a non-utilizable form.
- Taxon
- sunflower plantsHelianthus annuuse0
- Organ / stage
- vascular tissuee1
- Outcome
- immobility of boron in the leavese1
- Qualifier
- some type of translocation block in the vascular tissuee1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“boron by sunflower plants (Helianthus annuus L.) grown under controlled-environment conditions”
e1“It is further proposed that immobility of boron in the leaves of this species results from some type of translocation block in the vascular tissue”
The same questions in other papers
boron atom · growth · Helianthus annuus (common sunflower)Results differ
5 papers in the same direction as this paper · 33 reporting no difference from an alternative
- positive
- positive
- positive
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See all 39 papers →aluminium atom · nutrient: content · Helianthus annuus (common sunflower)Results agree
2 papers in the same direction as this paper
- negative
- no effect
irrigation · nutrient: content · Helianthus annuus (common sunflower)Positive and negative results
2 papers in the same direction as this paper · 3 in the opposite direction
- positive
- positive
- positive
2 papers more in this group
See all 6 papers →nitrogen · nutrient: content · Helianthus annuus (common sunflower)Positive and negative results
19 papers in the same direction as this paper · 2 in the opposite direction
This paper is about lacking the nutrient, so it counts the other way round here.
- no effect
- negative
- positive
18 papers more in this group
See all 22 papers →fertilization · nutrient: content · Helianthus annuus (common sunflower)Positive and negative results
6 papers in the same direction as this paper · 64 in the opposite direction
- positive
- positive
- positive
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See all 71 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.