Abstract
Mean nuclear 2C DNA content (C equaling haploid DNA per nucleus) of the first leaf of the sunflower, Helianthus annuus L., is influenced by the quality and the quantity of light. Seedlings of two inbred lines, RHA 299 and RHA 271 were germinated and grown in controlled environmental conditions. Lighting was adjusted to provide different combinations of photon flux densities and red to far red (R:FR) ratios. At R:FR = 5.8 and photon flux densities of 170 mumol.m-2.s-1, 200 mumol.m-2.s-1, and 230 mumol.m-2.s-1, DNA content remained high and relatively constant (x = 6.97 pg for RHA 271 and x = 7.32 pg for RHA 299). When the photon flux density range (R:FR = 5.8) was elevated to 350 mumol.m-2.s-1, 410 mumol.m-2.s-1, and 470 mumol.m-2.s-1, mean DNA content was reduced to 6.23 pg (RHA 271) and 6.46 pg (RHA 299). At R:FR = 1.5, mean DNA content was consistently high (7.2-7.9 pg) only at the lowest photon flux density of 170 mumol.m-2.s-1. Significant decreases in DNA content (< or = 12%) were observed at photon flux densities of 200 mumol.m-2.s-1 and 230 mumol.m-2.s-1. At the higher photon flux densities (350 mumol.m-2.s-1, 410 mumol.m-2.s-1, and 470 mumol.m-2.s-1) and R:RF = 1.5, the plants had extremely low DNA contents (mean x = 3.36 pg for RHA 271 and 3.41 pg for RHA 299) and high between-plant variance. The instability of DNA content, particularly for plants grown under light that is far red rich, suggests that phytochromes may be involved in regulating DNA content of the sunflower.
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Claims 10
Claim · model-written summary
At R:FR 5.8 and lower photon flux densities, RHA 271 DNA content stayed high at 6.97 pg.
- Taxon
- Helianthus annuus L.
Helianthus annuuse0 - Material
- RHA 271e1
- Treatment
- R:FR = 5.8 and photon flux densities of 170 mumol.m-2.s-1, 200 mumol.m-2.s-1, and 230 mumol.m-2.s-1e1
- Outcome
- DNA contente1
- Direction
- remained high and relatively constante1
- Value
- 6.97 pge1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Helianthus annuus L.”
e1“At R:FR = 5.8 and photon flux densities of 170 mumol.m-2.s-1, 200 mumol.m-2.s-1, and 230 mumol.m-2.s-1, DNA content remained high and relatively constant (x = 6.97 pg for RHA 271 and x = 7.32 pg for RHA 299).”
Claim · model-written summary
At R:FR 5.8 and lower photon flux densities, RHA 299 DNA content stayed high at 7.32 pg.
- Taxon
- Helianthus annuus L.Helianthus annuuse0
- Material
- RHA 299e1
- Treatment
- R:FR = 5.8 and photon flux densities of 170 mumol.m-2.s-1, 200 mumol.m-2.s-1, and 230 mumol.m-2.s-1e1
- Outcome
- DNA contente1
- Direction
- remained high and relatively constante1
- Value
- 7.32 pge1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Helianthus annuus L.”
e1“At R:FR = 5.8 and photon flux densities of 170 mumol.m-2.s-1, 200 mumol.m-2.s-1, and 230 mumol.m-2.s-1, DNA content remained high and relatively constant (x = 6.97 pg for RHA 271 and x = 7.32 pg for RHA 299).”
Claim · model-written summary
At higher photon flux density and R:FR 5.8, RHA 271 DNA content fell to 6.23 pg.
- Taxon
- Helianthus annuus L.Helianthus annuuse0
- Material
- RHA 271e1
- Treatment
- 350 mumol.m-2.s-1, 410 mumol.m-2.s-1, and 470 mumol.m-2.s-1e1
- Outcome
- mean DNA contente1
- Direction
- reducede1
- Value
- 6.23 pge1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Helianthus annuus L.”
e1“When the photon flux density range (R:FR = 5.8) was elevated to 350 mumol.m-2.s-1, 410 mumol.m-2.s-1, and 470 mumol.m-2.s-1, mean DNA content was reduced to 6.23 pg (RHA 271) and 6.46 pg (RHA 299).”
Claim · model-written summary
At higher photon flux density and R:FR 5.8, RHA 299 DNA content fell to 6.46 pg.
- Taxon
- Helianthus annuus L.Helianthus annuuse0
- Material
- RHA 299e1
- Treatment
- 350 mumol.m-2.s-1, 410 mumol.m-2.s-1, and 470 mumol.m-2.s-1e1
- Outcome
- mean DNA contente1
- Direction
- reducede1
- Value
- 6.46 pge1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Helianthus annuus L.”
e1“When the photon flux density range (R:FR = 5.8) was elevated to 350 mumol.m-2.s-1, 410 mumol.m-2.s-1, and 470 mumol.m-2.s-1, mean DNA content was reduced to 6.23 pg (RHA 271) and 6.46 pg (RHA 299).”
Claim · model-written summary
At R:FR 1.5, DNA content was consistently high at 7.2-7.9 pg only at the lowest photon flux density.
- Taxon
- Helianthus annuus L.Helianthus annuuse0
- Treatment
- R:FR = 1.5e1
- Outcome
- mean DNA contente1
- Direction
- consistently highe1
- Value
- 7.2-7.9 pge1
- Qualifier
- lowest photon flux density of 170 mumol.m-2.s-1e1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Helianthus annuus L.”
e1“At R:FR = 1.5, mean DNA content was consistently high (7.2-7.9 pg) only at the lowest photon flux density of 170 mumol.m-2.s-1.”
Claim · model-written summary
At R:FR 1.5, photon flux densities of 200 and 230 mumol.m-2.s-1 significantly reduced DNA content by up to 12%.
- Taxon
- Helianthus annuus L.Helianthus annuuse0
- Treatment
- photon flux densities of 200 mumol.m-2.s-1 and 230 mumol.m-2.s-1e1
- Outcome
- DNA contente1
- Direction
- decreasese1
- Value
- < or = 12%e1
- Qualifier
- R:FR = 1.5e2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Helianthus annuus L.”
e1“Significant decreases in DNA content (< or = 12%) were observed at photon flux densities of 200 mumol.m-2.s-1 and 230 mumol.m-2.s-1.”
e2“At R:FR = 1.5”
Claim · model-written summary
At high photon flux densities and R:RF 1.5, RHA 271 had extremely low DNA content averaging 3.36 pg.
- Taxon
- Helianthus annuus L.Helianthus annuuse0
- Material
- RHA 271e1
- Treatment
- higher photon flux densities (350 mumol.m-2.s-1, 410 mumol.m-2.s-1, and 470 mumol.m-2.s-1) and R:RF = 1.5e1
- Outcome
- DNA contentse1
- Direction
- extremely lowe1
- Value
- 3.36 pge1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Helianthus annuus L.”
e1“At the higher photon flux densities (350 mumol.m-2.s-1, 410 mumol.m-2.s-1, and 470 mumol.m-2.s-1) and R:RF = 1.5, the plants had extremely low DNA contents (mean x = 3.36 pg for RHA 271 and 3.41 pg for RHA 299) and high between-plant variance.”
Claim · model-written summary
At high photon flux densities and R:RF 1.5, RHA 299 had extremely low DNA content averaging 3.41 pg.
- Taxon
- Helianthus annuus L.Helianthus annuuse0
- Material
- RHA 299e1
- Treatment
- higher photon flux densities (350 mumol.m-2.s-1, 410 mumol.m-2.s-1, and 470 mumol.m-2.s-1) and R:RF = 1.5e1
- Outcome
- DNA contentse1
- Direction
- extremely lowe1
- Value
- 3.41 pge1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Helianthus annuus L.”
e1“At the higher photon flux densities (350 mumol.m-2.s-1, 410 mumol.m-2.s-1, and 470 mumol.m-2.s-1) and R:RF = 1.5, the plants had extremely low DNA contents (mean x = 3.36 pg for RHA 271 and 3.41 pg for RHA 299) and high between-plant variance.”
Claim · model-written summary
The high-light, low R:RF plants showed high between-plant variance in DNA content.
- Taxon
- Helianthus annuus L.Helianthus annuuse0
- Treatment
- higher photon flux densities (350 mumol.m-2.s-1, 410 mumol.m-2.s-1, and 470 mumol.m-2.s-1) and R:RF = 1.5e1
- Outcome
- high between-plant variancee1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Helianthus annuus L.”
e1“At the higher photon flux densities (350 mumol.m-2.s-1, 410 mumol.m-2.s-1, and 470 mumol.m-2.s-1) and R:RF = 1.5, the plants had extremely low DNA contents (mean x = 3.36 pg for RHA 271 and 3.41 pg for RHA 299) and high between-plant variance.”
Claim · model-written summary
The authors suggest phytochromes may regulate sunflower DNA content under far-red-rich light.
- Taxon
- sunflowerHelianthus annuuse0
- Gene
- phytochromese0
- Outcome
- DNA contente0
- Qualifier
- particularly for plants grown under light that is far red riche0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The instability of DNA content, particularly for plants grown under light that is far red rich, suggests that phytochromes may be involved in regulating DNA content of the sunflower.”
The same questions in other papers
light · molecular: metabolites · Helianthus annuus (common sunflower)Positive and negative results
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See all 11 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.