Abstract
Effects of irradiance on changes in the amounts of chlorophyll (Chl) and light-harvesting chlorophyll a/b protein of PS II (LHCII) were examined in senescing leaves of rice (Oryza sativa L.). Results of treatments at two irradiances (100% and 20% natural sunlight) were examined after the full expansion of the 13th leaf throughout the course of senescence. With 20% sunlight, the Chl content decreased only a little during leaf senescence, while with 100% sunlight it decreased appreciably. Similarly, the amount of LHCII protein during treatment with 20% sunlight remained almost constant. However, the ratio of Chl a/b during the shade treatment decreased significantly and the rate of decrease was greater than during the full-sunlight treatment. The ratio of Chl a/b for Chl a and b bound to LHCII was about 1.2, irrespective of leaf age or irradiance treatment. When the amounts of Chl bound to LHCII were calculated from the total leaf content of Chl and the ratio of Chl a/b, assuming a ratio of Chl a/b bound to LHCII of 1.2, they were well correlated with the amounts of LHCII protein. Changes in the amounts of LHCII synthesized during the two irradiance treatments were examined using an 15 tracer. Incorporation of 15N into LHCII declined dramatically during both treatments from full expansion through senescence, suggesting that there was little synthesis of LHCII protein during that time. In addition, the amount of LHCII synthesized during senescence was lower during the shade treatment than during the 100% sunlight treatment. These results indicate that the absence of an apparent change in levels of LHCII with shade treatment during senescence was caused by the very low rate of turnover of LHCII protein.
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Claims 9
Claim · model-written summary
Under 20% sunlight chlorophyll content decreased only a little during senescence, whereas under 100% sunlight it decreased appreciably.
- Taxon
- rice (Oryza sativa L.)
Oryza sativae0 - Organ / stage
- senescing leavese0
- Treatment
- 20% sunlighte1
- Outcome
- Chl contente1
- Direction
- decreased only a littlee1
- Comparator
- 100% sunlighte1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Effects of irradiance on changes in the amounts of chlorophyll (Chl) and light-harvesting chlorophyll a/b protein of PS II (LHCII) were examined in senescing leaves of rice (Oryza sativa L.)”
e1“With 20% sunlight, the Chl content decreased only a little during leaf senescence, while with 100% sunlight it decreased appreciably”
Claim · model-written summary
Under 20% sunlight the amount of LHCII protein remained almost constant during senescence.
- Taxon
- rice (Oryza sativa L.)Oryza sativae0
- Organ / stage
- senescing leavese0
- Treatment
- 20% sunlighte2
- Gene
- LHCII proteine2
- Outcome
- amount of LHCII proteine2
- Direction
- no_changeinferrede2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Effects of irradiance on changes in the amounts of chlorophyll (Chl) and light-harvesting chlorophyll a/b protein of PS II (LHCII) were examined in senescing leaves of rice (Oryza sativa L.)”
e2“Similarly, the amount of LHCII protein during treatment with 20% sunlight remained almost constant”
Claim · model-written summary
The Chl a/b ratio decreased significantly during the shade treatment.
- Taxon
- rice (Oryza sativa L.)Oryza sativae0
- Organ / stage
- senescing leavese0
- Treatment
- shade treatmente3
- Outcome
- ratio of Chl a/be3
- Direction
- decreasede3
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Effects of irradiance on changes in the amounts of chlorophyll (Chl) and light-harvesting chlorophyll a/b protein of PS II (LHCII) were examined in senescing leaves of rice (Oryza sativa L.)”
e3“However, the ratio of Chl a/b during the shade treatment decreased significantly and the rate of decrease was greater than during the full-sunlight treatment”
Claim · model-written summary
The rate of decrease of the Chl a/b ratio was greater during the shade treatment than during the full-sunlight treatment.
- Taxon
- rice (Oryza sativa L.)Oryza sativae0
- Organ / stage
- senescing leavese0
- Treatment
- shade treatmente3
- Outcome
- rate of decreasee3
- Direction
- greatere3
- Comparator
- full-sunlight treatmente3
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Effects of irradiance on changes in the amounts of chlorophyll (Chl) and light-harvesting chlorophyll a/b protein of PS II (LHCII) were examined in senescing leaves of rice (Oryza sativa L.)”
e3“However, the ratio of Chl a/b during the shade treatment decreased significantly and the rate of decrease was greater than during the full-sunlight treatment”
Claim · model-written summary
The Chl a/b ratio for Chl bound to LHCII was about 1.2 irrespective of leaf age or irradiance.
- Taxon
- rice (Oryza sativa L.)Oryza sativae0
- Outcome
- ratio of Chl a/b for Chl a and b bound to LHCIIe4
- Value
- about 1.2e4
- Qualifier
- irrespective of leaf age or irradiance treatmente4
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Effects of irradiance on changes in the amounts of chlorophyll (Chl) and light-harvesting chlorophyll a/b protein of PS II (LHCII) were examined in senescing leaves of rice (Oryza sativa L.)”
e4“The ratio of Chl a/b for Chl a and b bound to LHCII was about 1.2, irrespective of leaf age or irradiance treatment”
Claim · model-written summary
Chl bound to LHCII was well correlated with the amount of LHCII protein.
- Taxon
- rice (Oryza sativa L.)Oryza sativae0
- Gene
- LHCII proteine5
- Outcome
- amounts of Chl bound to LHCIIe5
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Effects of irradiance on changes in the amounts of chlorophyll (Chl) and light-harvesting chlorophyll a/b protein of PS II (LHCII) were examined in senescing leaves of rice (Oryza sativa L.)”
e5“When the amounts of Chl bound to LHCII were calculated from the total leaf content of Chl and the ratio of Chl a/b, assuming a ratio of Chl a/b bound to LHCII of 1.2, they were well correlated with the amounts of LHCII protein”
Claim · model-written summary
Incorporation of 15N into LHCII declined dramatically during both treatments from full expansion through senescence.
- Taxon
- rice (Oryza sativa L.)Oryza sativae0
- Treatment
- both treatmentse6
- Gene
- LHCII proteine6
- Outcome
- Incorporation of 15N into LHCIIe6
- Direction
- declined dramaticallye6
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Effects of irradiance on changes in the amounts of chlorophyll (Chl) and light-harvesting chlorophyll a/b protein of PS II (LHCII) were examined in senescing leaves of rice (Oryza sativa L.)”
e6“Incorporation of 15N into LHCII declined dramatically during both treatments from full expansion through senescence, suggesting that there was little synthesis of LHCII protein during that time”
Claim · model-written summary
The amount of LHCII synthesized during senescence was lower under shade than under 100% sunlight.
- Taxon
- rice (Oryza sativa L.)Oryza sativae0
- Treatment
- shade treatmente7
- Gene
- LHCIIe7
- Outcome
- amount of LHCII synthesized during senescencee7
- Direction
- lowere7
- Comparator
- 100% sunlight treatmente7
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Effects of irradiance on changes in the amounts of chlorophyll (Chl) and light-harvesting chlorophyll a/b protein of PS II (LHCII) were examined in senescing leaves of rice (Oryza sativa L.)”
e7“In addition, the amount of LHCII synthesized during senescence was lower during the shade treatment than during the 100% sunlight treatment”
Claim · model-written summary
The authors attribute the lack of an apparent change in LHCII levels under shade during senescence to a very low LHCII turnover rate.
- Taxon
- rice (Oryza sativa L.)Oryza sativae0
- Outcome
- absence of an apparent change in levels of LHCIIe1
- Qualifier
- caused by the very low rate of turnover of LHCII proteine1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Effects of irradiance on changes in the amounts of chlorophyll (Chl) and light-harvesting chlorophyll a/b protein of PS II (LHCII) were examined in senescing leaves of rice (Oryza sativa L.)”
e1“These results indicate that the absence of an apparent change in levels of LHCII with shade treatment during senescence was caused by the very low rate of turnover of LHCII protein”
The same questions in other papers
light · physiology: pigments · Oryza sativa (rice)Positive and negative results
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See all 16 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.