Abstract
A pH microelectrode has been used to investigate the auxin effect on free space pH and its correlation with auxin-stimulated elongation in segments of pea (Pisum sativum) stem and maize (Zea mays var. Bear Hybrid) coleoptile tissue. Auxin induces a decrease in free space pH in both tissues. In maize coleoptiles, free space pH begins to fall within about 12 minutes of exposure to auxin and decreases by about 1 pH unit by approximately 30 minutes. In pea, pH begins to decrease within an average of 15 to 18 minutes of exposure to auxin and falls by about 0.9 pH unit by approximately 40 minutes. Auxin-stimulated elongation, measured in the same two tissues similarly prepared, appears in maize at the earliest 18 minutes after auxin application, while in pea it appears at the earliest 21 to 24 minutes after auxin application. The auxin analogs p-chlorophenoxyisobutyric acid and phenylacetic acid do not stimulate elongation above control levels in maize or pea tissue segments and do not cause a decrease in free space pH in either tissue. These findings are consistent with the acid secretion theory of auxin action.
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Claims 7
Claim · model-written summary
Auxin decreased free space pH in maize coleoptiles by about one unit by approximately 30 minutes.
- Organ / stage
- coleoptilese0
- Treatment
- auxine0
- Outcome
- free space pHe0
- Direction
- decreasese0
- Value
- about 1 pH unite0
- Qualifier
- approximately 30 minutese0
Zea maysNot reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“In maize coleoptiles, free space pH begins to fall within about 12 minutes of exposure to auxin and decreases by about 1 pH unit by approximately 30 minutes.”
Claim · model-written summary
Auxin decreased free space pH in pea by about 0.9 unit by approximately 40 minutes.
- Taxon
- pea
Lathyrus oleraceuse0 - Treatment
- auxine0
- Outcome
- pHe0
- Direction
- fallse0
- Value
- about 0.9 pH unite0
- Qualifier
- approximately 40 minutese0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“In pea, pH begins to decrease within an average of 15 to 18 minutes of exposure to auxin and falls by about 0.9 pH unit by approximately 40 minutes.”
Claim · model-written summary
Auxin stimulated maize elongation from as early as 18 minutes.
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Auxin-stimulated elongation, measured in the same two tissues similarly prepared, appears in maize at the earliest 18 minutes after auxin application”
Claim · model-written summary
Auxin stimulated pea elongation from as early as 21 to 24 minutes.
- Taxon
- peaLathyrus oleraceuse0
- Treatment
- auxine0
- Outcome
- elongatione0
- Value
- 21 to 24 minutese0
Not reportedComparatorDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Auxin-stimulated elongation, measured in the same two tissues similarly prepared, appears in maize at the earliest 18 minutes after auxin application, while in pea it appears at the earliest 21 to 24 minutes after auxin application.”
Claim · model-written summary
The two auxin analogs did not stimulate elongation above controls in maize.
- Treatment
- p-chlorophenoxyisobutyric acid and phenylacetic acide0
- Outcome
- elongatione0
- Direction
- do not stimulatee0
- Comparator
- control levelse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The auxin analogs p-chlorophenoxyisobutyric acid and phenylacetic acid do not stimulate elongation above control levels in maize or pea tissue segments”
Claim · model-written summary
The two auxin analogs did not stimulate elongation above controls in pea.
- Taxon
- peaLathyrus oleraceuse0
- Treatment
- p-chlorophenoxyisobutyric acid and phenylacetic acide0
- Outcome
- elongatione0
- Direction
- do not stimulatee0
- Comparator
- control levelse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The auxin analogs p-chlorophenoxyisobutyric acid and phenylacetic acid do not stimulate elongation above control levels in maize or pea tissue segments”
Claim · model-written summary
The auxin analogs did not decrease free space pH in either maize or pea tissue.
Not reportedTaxonTreatmentComparator
Verbatim
e0“do not cause a decrease in free space pH in either tissue.”
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See all 68 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.