Abstract
The role of phytochrome in control of stem elongation by daily temperature alternations is unclear. The aim of this work was to study the involvement of phytochrome B in thermoperiodism in cucumber ( Cucumis sativus L.), and the interaction with gibberellin (GA). The wild type and the phytochrome B deficient, long-hypocotyl ( lh ) cucumber mutant were grown under alternating day (DT) and night temperature (NT) and either with or without an exposure to end-of-day far-red light (EOD-FR). Without EOD-FR, hypocotyl and internodes of the wild type plants were shorter under a low DT (19 °C)/high NT (25 °C) (negative DIF) compared with a high DT/low NT regime (positive DIF), while the number of leaves was reduced by 12%. EOD-FR enhanced elongation of hypocotyl and internodes. However, EOD-FR reduced the effect of alternating temperature on hypocotyl elongation. The lh cucumber mutant did not respond to EOD-FR treatments, but internode length was slightly increased by positive compared with negative DIF. The results suggest that phytochrome B is required for a maximum effect of daily temperature alternations on stem elongation in cucumber. Additional GA 4 reduced the difference between positive and negative DIF, but it had a minor effect only on the difference between EOD-FR and EOD red light (EOD-R) in the wild type. Plants depleted for endogenous GA by the GA biosynthesis inhibitor paclobutrazol, did not respond at all to DIF or EOD treatments. When seedlings were treated with prohexadione-calcium, which blocks both biosynthesis and inactivation of GA 4 , response to applied GA 4 was enhanced by EOD-FR. The present results suggest that, in cucumber, EOD-FR, and probably also positive DIF, enhances tissue sensitivity to GA 4 . In addition, catabolism of GA 4 can be enhanced by negative DIF.
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Claims 11
Claim · model-written summary
Hypocotyl and internodes of wild-type cucumber were shorter under negative DIF than under positive DIF.
- Taxon
- cucumber
Cucumis sativuse0 - Treatment
- negative DIFe1
- Outcome
- hypocotyl and internodese1
- Direction
- shortere1
- Comparator
- positive DIFe1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The aim of this work was to study the involvement of phytochrome B in thermoperiodism in cucumber ( Cucumis sativus L.)”
e1“Without EOD-FR, hypocotyl and internodes of the wild type plants were shorter under a low DT (19 °C)/high NT (25 °C) (negative DIF) compared with a high DT/low NT regime (positive DIF), while the number of leaves was reduced by 12%”
Claim · model-written summary
Negative DIF reduced the number of leaves of wild-type cucumber by 12%.
- Taxon
- cucumberCucumis sativuse0
- Treatment
- negative DIFe1
- Outcome
- number of leavese1
- Direction
- reducede1
- Value
- 12%e1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The aim of this work was to study the involvement of phytochrome B in thermoperiodism in cucumber ( Cucumis sativus L.)”
e1“Without EOD-FR, hypocotyl and internodes of the wild type plants were shorter under a low DT (19 °C)/high NT (25 °C) (negative DIF) compared with a high DT/low NT regime (positive DIF), while the number of leaves was reduced by 12%”
Claim · model-written summary
EOD-FR enhanced elongation of hypocotyl and internodes in cucumber.
- Taxon
- cucumberCucumis sativuse0
- Treatment
- EOD-FRe2
- Outcome
- elongation of hypocotyl and internodese2
- Direction
- enhancede2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The aim of this work was to study the involvement of phytochrome B in thermoperiodism in cucumber ( Cucumis sativus L.)”
e2“EOD-FR enhanced elongation of hypocotyl and internodes”
Claim · model-written summary
EOD-FR reduced the effect of alternating temperature on hypocotyl elongation.
- Taxon
- cucumberCucumis sativuse0
- Treatment
- EOD-FRe3
- Outcome
- effect of alternating temperature on hypocotyl elongatione3
- Direction
- reducede3
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The aim of this work was to study the involvement of phytochrome B in thermoperiodism in cucumber ( Cucumis sativus L.)”
e3“However, EOD-FR reduced the effect of alternating temperature on hypocotyl elongation”
Claim · model-written summary
The lh cucumber mutant did not respond to EOD-FR treatments.
- Taxon
- cucumberCucumis sativuse0
- Material
- lh cucumber mutante4
- Treatment
- EOD-FRe4
- Outcome
- respond to EOD-FR treatmentse4
Not reportedComparatorDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The aim of this work was to study the involvement of phytochrome B in thermoperiodism in cucumber ( Cucumis sativus L.)”
e4“The lh cucumber mutant did not respond to EOD-FR treatments”
Claim · model-written summary
Internode length of the lh cucumber mutant was slightly increased by positive compared with negative DIF.
- Taxon
- cucumberCucumis sativuse0
- Treatment
- positivee5
- Outcome
- internode lengthe5
- Direction
- slightly increasede5
- Comparator
- negative DIFe5
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The aim of this work was to study the involvement of phytochrome B in thermoperiodism in cucumber ( Cucumis sativus L.)”
e5“but internode length was slightly increased by positive compared with negative DIF”
Claim · model-written summary
Additional GA4 reduced the difference between positive and negative DIF in cucumber.
- Taxon
- cucumberCucumis sativuse0
- Treatment
- Additional GA 4e6
- Compound
- GA 4e6
- Outcome
- difference between positive and negative DIFe6
- Direction
- reducede6
- Comparator
- negative DIFe6
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The aim of this work was to study the involvement of phytochrome B in thermoperiodism in cucumber ( Cucumis sativus L.)”
e6“Additional GA 4 reduced the difference between positive and negative DIF, but it had a minor effect only on the difference between EOD-FR and EOD red light (EOD-R) in the wild type”
Claim · model-written summary
Plants depleted of endogenous GA by paclobutrazol did not respond to DIF or EOD treatments.
- Taxon
- cucumberCucumis sativuse0
- Treatment
- paclobutrazole7
- Outcome
- respond at all to DIF or EOD treatmentse7
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The aim of this work was to study the involvement of phytochrome B in thermoperiodism in cucumber ( Cucumis sativus L.)”
e7“Plants depleted for endogenous GA by the GA biosynthesis inhibitor paclobutrazol, did not respond at all to DIF or EOD treatments”
Claim · model-written summary
EOD-FR enhanced the response of prohexadione-calcium-treated seedlings to applied GA4.
- Taxon
- cucumberCucumis sativuse0
- Treatment
- EOD-FRe1
- Compound
- GA 4e1
- Outcome
- response to applied GA 4e1
- Direction
- enhancede1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The aim of this work was to study the involvement of phytochrome B in thermoperiodism in cucumber ( Cucumis sativus L.)”
e1“When seedlings were treated with prohexadione-calcium, which blocks both biosynthesis and inactivation of GA 4 , response to applied GA 4 was enhanced by EOD-FR”
Claim · model-written summary
EOD-FR, and probably also positive DIF, enhances tissue sensitivity to GA4 in cucumber.
- Taxon
- cucumberCucumis sativuse1
- Treatment
- EOD-FRe1
- Compound
- GA 4e1
- Outcome
- tissue sensitivity to GA 4e1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“The present results suggest that, in cucumber, EOD-FR, and probably also positive DIF, enhances tissue sensitivity to GA 4”
Claim · model-written summary
Negative DIF can enhance catabolism of GA4 in cucumber.
- Taxon
- cucumberCucumis sativuse0
- Treatment
- negative DIFe1
- Compound
- GA 4e1
- Outcome
- catabolism of GA 4e1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The aim of this work was to study the involvement of phytochrome B in thermoperiodism in cucumber ( Cucumis sativus L.)”
e1“In addition, catabolism of GA 4 can be enhanced by negative DIF”
The same questions in other papers
light · molecular: metabolites · Cucumis sativus (cucumber)Positive and negative results
11 papers in the same direction as this paper · 10 in the opposite direction · 1 reporting no difference from an alternative
- no effect
- negative
- negative
19 papers more in this group
See all 23 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.