Abstract
The effect of removal of the shoot apex of 92-d-old tobacco plants and its replacement by 1-naphthylacetic acid (NAA) on sink-source relationships and on the flows and partitioning of potassium and water has been studied over a short-term period of 7 d (intact control plants) or 8 d (decapitated and NAA-treated plants). For determining flows an upper, middle and lower stratum of three leaves each were analysed. Within the study period three new leaves were formed in control plants and 57.7% of the total dry matter increment during the experimental period was allocated to the apex and these newly formed leaves. An even higher proportion of the K+ taken up (93.8%) was deposited in these organs and this was imported via xylem (72%) and phloem (28%). Only 18.7% and 9.8% of the total dry matter increment were found in the previously present upper leaves and the roots, respectively, and substantial net K+ export occurred from middle and lower leaves and roots. Decapitation removed the dominant phloem sink and caused marked changes in sink-source relationships. After decapitation the net increase in root dry matter was twice that of control plants. 56.2% of the total net increments in dry matter and 70% of the absorbed K+ were deposited in upper leaves (below the excised apex). There was only slight net K+ export from the middle leaves. Application of NAA on the cut surface of the stem stump did not change the growth of plants that much, apart from a substantial increase in stem growth, correspondingly it stimulated the partitioning of K+ into the upper leaves and most dramatically into the stem, which deposited 64.5% or 27% of the K+ uptake, respectively. In these plants K+ uptake was increased and the K+ concentrations in upper, middle and lower leaves were increased from 4.7, 5.4 and 5.6 to 5.1, 6.1 and 6.1% of dry matter, respectively. Possible mechanisms of this effect of NAA on the improvement of K+ concentration in tobacco leaves are discussed in detail.
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Claims 19
Claim · model-written summary
In intact tobacco control plants 57.7% of the total dry matter increment was allocated to the apex and the newly formed leaves.
- Taxon
- tobacco
Nicotiana tabacumt0 - Organ / stage
- apex and these newly formed leavese1
- Outcome
- total dry matter incremente1
- Value
- 57.7%e1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“tobacco plants”
e1“57.7% of the total dry matter increment during the experimental period was allocated to the apex and these newly formed leaves”
Claim · model-written summary
In control plants 93.8% of the K+ taken up was deposited in the apex and the newly formed leaves.
- Taxon
- tobaccoNicotiana tabacumt0
- Organ / stage
- these organse1
- Outcome
- K+ taken upe1
- Value
- 93.8%e1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“tobacco plants”
e1“An even higher proportion of the K+ taken up (93.8%) was deposited in these organs”
Claim · model-written summary
K+ deposited in the apex and new leaves of control plants was imported via the xylem (72%).
- Taxon
- tobaccoNicotiana tabacumt0
- Outcome
- imported via xyleme1
- Value
- 72%e1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“tobacco plants”
e1“this was imported via xylem (72%)”
Claim · model-written summary
K+ deposited in the apex and new leaves of control plants was imported via the phloem (28%).
- Taxon
- tobaccoNicotiana tabacumt0
- Outcome
- phloeme1
- Value
- 28%e1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“tobacco plants”
e1“and phloem (28%)”
Claim · model-written summary
Only 18.7% of the total dry matter increment of control plants was found in the previously present upper leaves.
- Taxon
- tobaccoNicotiana tabacumt0
- Organ / stage
- previously present upper leavese1
- Outcome
- total dry matter incremente1
- Value
- 18.7%e1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“tobacco plants”
e1“Only 18.7% and 9.8% of the total dry matter increment were found in the previously present upper leaves”
Claim · model-written summary
Only 9.8% of the total dry matter increment of control plants was found in the roots.
- Taxon
- tobaccoNicotiana tabacumt0
- Organ / stage
- the rootse1
- Outcome
- total dry matter incremente1
- Value
- 9.8%e1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“tobacco plants”
e1“Only 18.7% and 9.8% of the total dry matter increment were found in the previously present upper leaves and the roots”
Claim · model-written summary
Substantial net K+ export occurred from middle and lower leaves and roots of control plants.
- Taxon
- tobaccoNicotiana tabacumt0
- Organ / stage
- middle and lower leaves and rootse1
- Outcome
- net K+ exporte1
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“tobacco plants”
e1“substantial net K+ export occurred from middle and lower leaves and roots”
Claim · model-written summary
After decapitation the net increase in root dry matter was twice that of control plants.
- Taxon
- tobaccoNicotiana tabacumt0
- Treatment
- decapitatione1
- Outcome
- net increase in root dry mattere1
- Direction
- twicee1
- Value
- twicee1
- Comparator
- control plantse1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“tobacco plants”
e1“After decapitation the net increase in root dry matter was twice that of control plants”
Claim · model-written summary
After decapitation 56.2% of the total net increment in dry matter was deposited in the upper leaves below the excised apex.
- Taxon
- tobaccoNicotiana tabacumt0
- Organ / stage
- upper leavese2
- Treatment
- decapitatione1
- Outcome
- total net increments in dry mattere2
- Value
- 56.2%e2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“tobacco plants”
e1“After decapitation”
e2“56.2% of the total net increments in dry matter and 70% of the absorbed K+ were deposited in upper leaves (below the excised apex)”
Claim · model-written summary
After decapitation 70% of the absorbed K+ was deposited in the upper leaves below the excised apex.
- Taxon
- tobaccoNicotiana tabacumt0
- Organ / stage
- upper leavese2
- Treatment
- decapitatione1
- Outcome
- absorbed K+e2
- Value
- 70%e2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“tobacco plants”
e1“After decapitation”
e2“56.2% of the total net increments in dry matter and 70% of the absorbed K+ were deposited in upper leaves (below the excised apex)”
Claim · model-written summary
There was only slight net K+ export from the middle leaves of decapitated plants.
- Taxon
- tobaccoNicotiana tabacumt0
- Organ / stage
- middle leavese1
- Outcome
- net K+ exporte1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“tobacco plants”
e1“There was only slight net K+ export from the middle leaves”
Claim · model-written summary
NAA applied on the cut stem stump caused a substantial increase in stem growth.
- Taxon
- tobaccoNicotiana tabacumt0
- Treatment
- Application of NAA on the cut surface of the stem stumpe1
- Outcome
- stem growthe1
- Direction
- increasee1
- Qualifier
- substantiale1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“tobacco plants”
e1“Application of NAA on the cut surface of the stem stump did not change the growth of plants that much, apart from a substantial increase in stem growth”
Claim · model-written summary
NAA applied on the cut stem stump did not change overall plant growth much apart from stem growth.
- Taxon
- tobaccoNicotiana tabacumt0
- Treatment
- Application of NAA on the cut surface of the stem stumpe1
- Outcome
- growth of plantse1
- Direction
- did not changee1
- Qualifier
- that muche1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“tobacco plants”
e1“Application of NAA on the cut surface of the stem stump did not change the growth of plants that much”
Claim · model-written summary
NAA stimulated the partitioning of K+ into the upper leaves, which deposited 64.5% of the K+ uptake.
- Taxon
- tobaccoNicotiana tabacumt0
- Organ / stage
- upper leavese2
- Treatment
- NAAe1
- Outcome
- partitioning of K+e2
- Direction
- stimulatede2
- Value
- 64.5%e2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“tobacco plants”
e1“Application of NAA on the cut surface of the stem stump”
e2“it stimulated the partitioning of K+ into the upper leaves and most dramatically into the stem, which deposited 64.5% or 27% of the K+ uptake, respectively”
Claim · model-written summary
NAA stimulated most dramatically the partitioning of K+ into the stem, which deposited 27% of the K+ uptake.
- Taxon
- tobaccoNicotiana tabacumt0
- Organ / stage
- steme2
- Treatment
- NAAe1
- Outcome
- partitioning of K+e2
- Direction
- stimulatede2
- Value
- 27%e2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“tobacco plants”
e1“Application of NAA on the cut surface of the stem stump”
e2“it stimulated the partitioning of K+ into the upper leaves and most dramatically into the stem, which deposited 64.5% or 27% of the K+ uptake, respectively”
Claim · model-written summary
In NAA-treated plants K+ uptake was increased.
- Taxon
- tobaccoNicotiana tabacumt0
- Treatment
- NAAe1
- Outcome
- K+ uptakee2
- Direction
- increasede2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“tobacco plants”
e1“Application of NAA on the cut surface of the stem stump”
e2“In these plants K+ uptake was increased”
Claim · model-written summary
In NAA-treated plants the K+ concentration in upper leaves increased from 4.7 to 5.1% of dry matter.
- Taxon
- tobaccoNicotiana tabacumt0
- Organ / stage
- uppere2
- Treatment
- NAAe1
- Outcome
- K+ concentrationse2
- Direction
- increasede2
- Value
- 5.1e2
- Qualifier
- from 4.7e2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“tobacco plants”
e1“Application of NAA on the cut surface of the stem stump”
e2“the K+ concentrations in upper, middle and lower leaves were increased from 4.7, 5.4 and 5.6 to 5.1, 6.1 and 6.1% of dry matter, respectively”
Claim · model-written summary
In NAA-treated plants the K+ concentration in middle leaves increased from 5.4 to 6.1% of dry matter.
- Taxon
- tobaccoNicotiana tabacumt0
- Organ / stage
- middlee2
- Treatment
- NAAe1
- Outcome
- K+ concentrationse2
- Direction
- increasede2
- Value
- 6.1e2
- Qualifier
- 5.4e2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“tobacco plants”
e1“Application of NAA on the cut surface of the stem stump”
e2“the K+ concentrations in upper, middle and lower leaves were increased from 4.7, 5.4 and 5.6 to 5.1, 6.1 and 6.1% of dry matter, respectively”
Claim · model-written summary
In NAA-treated plants the K+ concentration in lower leaves increased from 5.6 to 6.1% of dry matter.
- Taxon
- tobaccoNicotiana tabacumt0
- Organ / stage
- lower leavese2
- Treatment
- NAAe1
- Outcome
- K+ concentrationse2
- Direction
- increasede2
- Value
- 6.1% of dry mattere2
- Qualifier
- 5.6e2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“tobacco plants”
e1“Application of NAA on the cut surface of the stem stump”
e2“the K+ concentrations in upper, middle and lower leaves were increased from 4.7, 5.4 and 5.6 to 5.1, 6.1 and 6.1% of dry matter, respectively”
The same questions in other papers
1-naphthaleneacetic acid · growth · Nicotiana tabacum (tobacco)Results agree
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- positive
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15 papers in the same direction as this paper · 2 in the opposite direction
- no effect
- negative
- positive
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See all 18 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.