Abstract
In detached kohlrabi leaves senescing in the dark, the decrease in chlorophyll to was more pronounced than in chlorophyll a. The retardation by kinetin of the chlorophyll loss was also markedly stronger in the case of chlorophyll b. Using the fractionation of nucleic acids on polyacrylamide gels it has been shown that during leaf senescence the level of all RNA species decreased, whereas the amount of DNA was more or less constant. In the presence of kinetin, the loss of RNA was inhibited and the incorporation of precursor into the cytoplasmic rRNA as well as into low molecular weight RNA species was supported. Chloroplast rRNA synthesis has not been detected in mature leaves and kinetin showed no effect in this respect. In young expanding leaves detached and kept in light, the synthesis of cytoplasmic rRNA was strongly stimulated by kinetin, whereas in the case of Chloroplast rRNA only an inhibitory effect of kinetin could be found. The results suggest that the cytokinins are primarily involved in processes of the synthesis of cytoplasmic rRNA and low molecular RNA fractions, and in this way affect the development of plastids, in particular the course of their senescence.
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Claims 12
Claim · model-written summary
In dark senescing detached kohlrabi leaves, chlorophyll b declined more than chlorophyll a.
- Taxon
- kohlrabi
Brassica oleracea var. gongylodese0 - Organ / stage
- detached kohlrabi leavese0
- Outcome
- decrease in chlorophyll toe0
- Direction
- more pronouncede0
- Comparator
- chlorophyll ae0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“In detached kohlrabi leaves senescing in the dark, the decrease in chlorophyll to was more pronounced than in chlorophyll a”
Claim · model-written summary
Kinetin retarded chlorophyll b loss more strongly than chlorophyll a loss.
- Taxon
- Brassica oleracea L. var. gongylodes L.Brassica oleracea var. gongylodest0
- Organ / stage
- chlorophyll be0
- Treatment
- kinetine0
- Outcome
- chlorophyll losse0
- Direction
- retardatione0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The retardation by kinetin of the chlorophyll loss was also markedly stronger in the case of chlorophyll b”
t0“Brassica oleracea L. var. gongylodes L.”
Claim · model-written summary
All RNA species decreased during leaf senescence.
- Taxon
- Brassica oleracea L. var. gongylodes L.Brassica oleracea var. gongylodest0
- Organ / stage
- leaf senescencee0
- Outcome
- level of all RNA speciese0
- Direction
- decreasede0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“during leaf senescence the level of all RNA species decreased”
t0“Brassica oleracea L. var. gongylodes L.”
Claim · model-written summary
DNA amount remained approximately constant during leaf senescence.
- Taxon
- Brassica oleracea L. var. gongylodes L.Brassica oleracea var. gongylodest0
- Outcome
- amount of DNAe0
- Direction
- more or less constante0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“whereas the amount of DNA was more or less constant”
t0“Brassica oleracea L. var. gongylodes L.”
Claim · model-written summary
Kinetin inhibited RNA loss.
- Taxon
- Brassica oleracea L. var. gongylodes L.Brassica oleracea var. gongylodest0
- Treatment
- kinetine0
- Outcome
- loss of RNAe0
- Direction
- inhibitede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“In the presence of kinetin, the loss of RNA was inhibited”
t0“Brassica oleracea L. var. gongylodes L.”
Claim · model-written summary
Kinetin supported precursor incorporation into cytoplasmic rRNA.
- Taxon
- Brassica oleracea L. var. gongylodes L.Brassica oleracea var. gongylodest0
- Treatment
- kinetine1
- Outcome
- incorporation of precursor into the cytoplasmic rRNAe0
- Direction
- supportede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the incorporation of precursor into the cytoplasmic rRNA as well as into low molecular weight RNA species was supported”
t0“Brassica oleracea L. var. gongylodes L.”
e1“In the presence of kinetin”
Claim · model-written summary
Kinetin supported precursor incorporation into low molecular weight RNA species.
- Taxon
- Brassica oleracea L. var. gongylodes L.Brassica oleracea var. gongylodest0
- Treatment
- kinetine1
- Outcome
- low molecular weight RNA speciese0
- Direction
- supportede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“into low molecular weight RNA species was supported”
t0“Brassica oleracea L. var. gongylodes L.”
e1“In the presence of kinetin”
Claim · model-written summary
Chloroplast rRNA synthesis was not detected in mature leaves.
- Taxon
- Brassica oleracea L. var. gongylodes L.Brassica oleracea var. gongylodest0
- Organ / stage
- mature leavese0
- Outcome
- Chloroplast rRNA synthesise0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Chloroplast rRNA synthesis has not been detected in mature leaves”
t0“Brassica oleracea L. var. gongylodes L.”
Claim · model-written summary
Kinetin did not affect chloroplast rRNA synthesis in mature leaves.
- Taxon
- Brassica oleracea L. var. gongylodes L.Brassica oleracea var. gongylodest0
- Treatment
- kinetine0
- Outcome
- Chloroplast rRNA synthesise1
- Direction
- no effecte0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“kinetin showed no effect in this respect”
t0“Brassica oleracea L. var. gongylodes L.”
e1“Chloroplast rRNA synthesis has not been detected in mature leaves”
Claim · model-written summary
Kinetin strongly stimulated cytoplasmic rRNA synthesis in detached young expanding leaves in light.
- Taxon
- Brassica oleracea L. var. gongylodes L.Brassica oleracea var. gongylodest0
- Organ / stage
- young expanding leavese0
- Treatment
- kinetine0
- Outcome
- synthesis of cytoplasmic rRNAe0
- Direction
- strongly stimulatede0
- Qualifier
- detached and kept in lighte0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“In young expanding leaves detached and kept in light, the synthesis of cytoplasmic rRNA was strongly stimulated by kinetin”
t0“Brassica oleracea L. var. gongylodes L.”
Claim · model-written summary
Kinetin inhibited chloroplast rRNA synthesis in young expanding leaves.
- Taxon
- Brassica oleracea L. var. gongylodes L.Brassica oleracea var. gongylodest0
- Organ / stage
- young expanding leavese1
- Treatment
- kinetine0
- Outcome
- Chloroplast rRNAe0
- Direction
- inhibitory effecte0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“in the case of Chloroplast rRNA only an inhibitory effect of kinetin could be found”
t0“Brassica oleracea L. var. gongylodes L.”
e1“In young expanding leaves detached and kept in light”
Claim · model-written summary
The authors suggest cytokinins primarily regulate cytoplasmic rRNA and low molecular RNA synthesis and thereby plastid senescence.
- Taxon
- Brassica oleracea L. var. gongylodes L.Brassica oleracea var. gongylodest0
- Outcome
- development of plastidse0
- Qualifier
- synthesis of cytoplasmic rRNA and low molecular RNA fractionse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the cytokinins are primarily involved in processes of the synthesis of cytoplasmic rRNA and low molecular RNA fractions, and in this way affect the development of plastids, in particular the course of their senescence”
t0“Brassica oleracea L. var. gongylodes L.”
The same questions in other papers
kinetin · physiology: pigments · Brassica oleracea (wild cabbage)Positive and negative results
2 papers in the same direction as this paper · 1 in the opposite direction
- negative
- positive
- positive
kinetin · molecular: metabolites · Brassica oleracea (wild cabbage)Results agree
1 paper in the same direction as this paper
- positive
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.