Abstract
The paper deals with the general problem of the physiological basis of branching, and the roles of known and unexplored factors in sensitivity to apical dominance. It is shown that when pea seedling shoots are completely or partially inhibited by other shoots on the same plant auxin can promote their elongation, even though it does not have this effect on inhibited buds. This influence of auxin is only exerted on internodal elongation and not on apical growth. When kinetin in a solution of alcohol and carbowax is applied directly to the lateral buds of pea seedlings, it releases them from inhibition by the growing apex. It is shown that the role of alcohol in this solution is to act as a surfactant, permitting good contact with the buds, while that of carbowax, being hygroscopic, is to maintain a thin film of solution over the buds. Buds thus released from apical dominance by kinetin do not elongate as much as do uninhibited control buds. Such kinetin-treated buds can, however, be made to elongate normally by the application of auxin locally to their apices. It is concluded that growing shoots are relatively insensitive to correlative inhibition because they synthesize two types of growth substances, namely, auxin, which antagonizes the inhibitory effect on internodal elongation, and cytokinins, which permit the apex itself to develop. In the discussion it is brought out that many cases of branching, which appear at first to bear little relation to one another, can be understood on the basis of two principles, namely: (1) Any reduction in the growth rate of a dominant apex reduces its inhibitory effect on other apices, and (2) once an apex starts growing it becomes less sensitive to inhibition by other apices These generalizations and the experimental results are tentatively interpreted in terms of an interaction between the syntheses of auxin and of cytoldnin.
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 8
Claim · model-written summary
Auxin promoted elongation of inhibited pea shoots.
- Taxon
- pea
Lathyrus oleraceuse0 - Treatment
- auxine0
- Outcome
- elongatione0
- Direction
- promotee0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“when pea seedling shoots are completely or partially inhibited by other shoots on the same plant auxin can promote their elongation”
Claim · model-written summary
Auxin did not promote elongation of inhibited buds.
- Taxon
- peaLathyrus oleraceuse1
- Treatment
- Auxinst0
- Outcome
- effect on inhibited budse0
- Direction
- does note0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“it does not have this effect on inhibited buds.”
t0“Auxins”
e1“pea seedlings”
Claim · model-written summary
Auxin acted on internodal elongation rather than apical growth.
- Taxon
- peaLathyrus oleraceuse1
- Organ / stage
- internodale0
- Outcome
- internodal elongatione0
- Direction
- only exertede0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“This influence of auxin is only exerted on internodal elongation and not on apical growth.”
t0“Auxins”
e1“pea seedlings”
Claim · model-written summary
Kinetin released lateral buds from inhibition by the apex.
- Taxon
- peaLathyrus oleraceuse0
- Treatment
- kinetin in a solution of alcohol and carbowaxe0
- Outcome
- inhibition by the growing apexe0
- Direction
- releasese0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“When kinetin in a solution of alcohol and carbowax is applied directly to the lateral buds of pea seedlings, it releases them from inhibition by the growing apex.”
Claim · model-written summary
Alcohol served as surfactant and carbowax maintained the solution film.
- Taxon
- peaLathyrus oleraceuse1
- Outcome
- good contact with the budse0
- Qualifier
- act as a surfactante0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the role of alcohol in this solution is to act as a surfactant, permitting good contact with the buds, while that of carbowax, being hygroscopic, is to maintain a thin film of solution over the buds.”
t0“Auxins”
e1“pea seedlings”
Claim · model-written summary
Kinetin-released buds elongated less than uninhibited buds.
- Taxon
- peaLathyrus oleraceuse1
- Treatment
- kinetine0
- Outcome
- elongatee0
- Direction
- do not elongate as muche0
- Comparator
- uninhibited control budse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Buds thus released from apical dominance by kinetin do not elongate as much as do uninhibited control buds.”
t0“Auxins”
e1“pea seedlings”
Claim · model-written summary
Local auxin restored normal elongation to kinetin-treated buds.
- Taxon
- peaLathyrus oleraceuse1
- Treatment
- application of auxin locally to their apicese0
- Outcome
- elongate normallye0
Not reportedComparatorDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Such kinetin-treated buds can, however, be made to elongate normally by the application of auxin locally to their apices.”
t0“Auxins”
e1“pea seedlings”
Claim · model-written summary
Authors concluded that shoot-produced auxin counteracts internodal inhibition and cytokinins enable apex development.
- Taxon
- peaLathyrus oleraceuse1
- Outcome
- internodal elongatione0
- Qualifier
- auxin, which antagonizes the inhibitory effecte0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“they synthesize two types of growth substances, namely, auxin, which antagonizes the inhibitory effect on internodal elongation, and cytokinins, which permit the apex itself to develop.”
t0“Auxins”
e1“pea seedlings”
The same questions in other papers
class · growth · Lathyrus oleraceus (pea)Positive and negative results
21 papers in the same direction as this paper · 15 in the opposite direction
- negative
- negative
- no effect
33 papers more in this group
See all 37 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.