Abstract
In this study, the content of active internal indolebutyric acid (IBA) and of IBA-derived indoleacetic acid (IAA) was related to adventitious root formation on the stem base of microcuttings of apple. Maximum root formation was obtained after an incubation of 3 days on medium supplemented with 32 μm IBA or 5 days on medium containing 3·2 or 10 μm of the hormone. Two to three weeks after the start of the auxin treatment, the maximum root number was attained. The absorbed IBA-3H accumulated predominantly in the bottom 1 mm of the stem, i.e. the location where the roots emerge. The metabolism of [3H]-IBA was examined in this part of the apple shoots in relation to adventitious root formation in vitro. The internal content of free IBA (IBAint) corresponded to about 60% of the IBA concentration in the medium from 6 h to 3 days of incubation. The internal content of IBA-derived IAA (IAAint) was about 15% of the IBA concentration in the medium. At incubation periods of 2 and 3 days the shorter period required a higher IBAint and IAAint content to produce the same amount of roots. This observation indicates that in those cases, the mode of action of IBA in root formation resembles a dose effect of the active auxin components in the stem base. Over the whole range of experimental conditions (6–120 h, 0·1–32 μm), however, the product of incubation time and exogenous concentration or internal content of auxins was not related to the number of roots. The percentage of label recovered in the IBAint and IAAint fractions was the same at suboptimal and optimal IBA concentrations for root formation, and did not change between 0·7 and 3 days after auxin addition. Therefore, root formation was not related to a specific type of auxin metabolism.
Abstract from the paper’s OpenAlex record, shown for indexing and research. Copyright remains with the authors or the publisher. Read at the source ↗
The text the model read, with the source record’s inline markup (italics, sub- and superscripts) rendered and its character entities decoded; quote offsets refer to the raw text.
Claims 13
Claim · model-written summary
Maximum root formation followed three days at 32 μm IBA.
- Taxon
- apple
Malus domesticae1 - Organ / stage
- microcuttingse1
- Treatment
- 3 days on medium supplemented with 32 μm IBAe0
- Outcome
- root formatione0
- Direction
- Maximume0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Maximum root formation was obtained after an incubation of 3 days on medium supplemented with 32 μm IBA”
e1“microcuttings of apple”
Claim · model-written summary
Maximum root formation also followed five days at 3·2 or 10 μm IBA.
- Taxon
- appleMalus domesticae2
- Treatment
- 5 days on medium containing 3·2 or 10 μm of the hormonee0
- Outcome
- root formatione1
- Direction
- Maximume1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“5 days on medium containing 3·2 or 10 μm of the hormone”
e1“Maximum root formation was obtained after an incubation of 3 days on medium supplemented with 32 μm IBA or 5 days on medium containing 3·2 or 10 μm of the hormone”
e2“microcuttings of apple”
Claim · model-written summary
Maximum root number was attained two to three weeks after auxin treatment began.
- Taxon
- appleMalus domesticae1
- Outcome
- root numbere0
- Direction
- maximume0
- Qualifier
- Two to three weeks after the start of the auxin treatmente0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Two to three weeks after the start of the auxin treatment, the maximum root number was attained”
e1“microcuttings of apple”
Claim · model-written summary
Absorbed IBA-3H accumulated mainly in the bottom 1 mm of stems.
- Taxon
- appleMalus domesticae1
- Organ / stage
- bottom 1 mm of the steme0
- Outcome
- absorbed IBA-3H accumulatede0
- Direction
- predominantlye0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The absorbed IBA-3H accumulated predominantly in the bottom 1 mm of the stem”
e1“apple shoots”
Claim · model-written summary
Internal free IBA was about 60% of medium IBA concentration from 6 h to 3 days.
- Taxon
- appleMalus domesticae1
- Outcome
- internal content of free IBA (IBAint)e0
- Value
- about 60%e0
- Qualifier
- from 6 h to 3 days of incubatione0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“internal content of free IBA (IBAint) corresponded to about 60% of the IBA concentration in the medium from 6 h to 3 days of incubation”
e1“apple shoots”
Claim · model-written summary
Internal IBA derived IAA was about 15% of medium IBA concentration.
- Taxon
- appleMalus domesticae1
- Outcome
- internal content of IBA-derived IAA (IAAint)e0
- Value
- about 15%e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“internal content of IBA-derived IAA (IAAint) was about 15% of the IBA concentration in the medium”
e1“apple shoots”
Claim · model-written summary
At two versus three incubation days, the shorter period required more internal IBA and IAA for the same root number.
- Taxon
- appleMalus domesticae1
- Outcome
- IBAint and IAAint contente0
- Direction
- highere0
- Qualifier
- same amount of rootse0
- Comparator
- 3 dayse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“At incubation periods of 2 and 3 days the shorter period required a higher IBAint and IAAint content to produce the same amount of roots”
e1“apple shoots”
Claim · model-written summary
For those incubation periods, authors interpreted root formation as resembling a dose effect of active auxins.
- Taxon
- appleMalus domesticae1
- Outcome
- root formatione0
- Qualifier
- dose effect of the active auxin components in the stem basee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“mode of action of IBA in root formation resembles a dose effect of the active auxin components in the stem base”
e1“apple shoots”
Claim · model-written summary
Across all conditions, time times exogenous auxin concentration was unrelated to root number.
- Taxon
- appleMalus domesticae2
- Treatment
- exogenous concentratione0
- Outcome
- number of rootse0
- Qualifier
- 6–120 h, 0·1–32 μme1
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“product of incubation time and exogenous concentration or internal content of auxins was not related to the number of roots”
e1“Over the whole range of experimental conditions (6–120 h, 0·1–32 μm)”
e2“apple shoots”
Claim · model-written summary
Across all conditions, time times internal auxin content was unrelated to root number.
- Taxon
- appleMalus domesticae1
- Compound
- internal content of auxinse0
- Outcome
- number of rootse0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“product of incubation time and exogenous concentration or internal content of auxins was not related to the number of roots”
e1“apple shoots”
Claim · model-written summary
Label recovery in internal IBA and IAA fractions was the same at suboptimal and optimal IBA concentrations.
- Taxon
- appleMalus domesticae1
- Outcome
- percentage of label recovered in the IBAint and IAAint fractionse0
- Direction
- samee0
- Comparator
- suboptimal and optimal IBA concentrationse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“percentage of label recovered in the IBAint and IAAint fractions was the same at suboptimal and optimal IBA concentrations”
e1“apple shoots”
Claim · model-written summary
Label recovery in internal IBA and IAA fractions did not change from 0·7 to 3 days.
- Taxon
- appleMalus domesticae1
- Outcome
- percentage of label recovered in the IBAint and IAAint fractionse0
- Direction
- did not changee0
- Qualifier
- between 0·7 and 3 days after auxin additione0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“percentage of label recovered in the IBAint and IAAint fractions was the same at suboptimal and optimal IBA concentrations for root formation, and did not change between 0·7 and 3 days after auxin addition”
e1“apple shoots”
Claim · model-written summary
Root formation was not related to a specific type of auxin metabolism.
- Taxon
- appleMalus domesticae1
- Compound
- auxine0
- Outcome
- root formatione0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“root formation was not related to a specific type of auxin metabolism”
e1“apple shoots”
The same questions in other papers
indole-3-butyric acid · growth · Malus domestica (apple)Results differ
35 papers in the same direction as this paper · 2 in the opposite direction
- positive
- positive
- negative
34 papers more in this group
See all 38 papers →in vitro · growth · Malus domestica (apple)Positive and negative results
33 papers in the same direction as this paper · 4 in the opposite direction
- positive
- negative
- no effect
34 papers more in this group
See all 38 papers →class · growth · Malus domestica (apple)Positive and negative results
37 papers in the same direction as this paper · 8 in the opposite direction
- negative
- negative
- no effect
42 papers more in this group
See all 46 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.