Abstract
The accumulation, distribution and redistribution of dry matter and nitrogen is described for Helianthus annuus L. cv. Hysun 21 grown on 6 mM urea in glasshouse culture. Seed dry matter and nitrogen were transferred to seedlings with net efficiencies of 40 and 86 per cent respectively. At flowering, the stem had most of the plant's dry matter and the leaves most of its nitrogen. About 35 per cent of the plant's nitrogen accumulated after three-row anthesis. The amount of protein in vegetative parts, especially leaves, declined after flowering. Concentrations of free amino compounds also decreased during growth. Mature seeds had 38 per cent of the total plant dry weight and 68 per cent of the total nitrogen. Seeds acquired 33 per cent of their dry matter and nitrogen from redistribution from above-ground plant parts. The stem was most important for storage of carbohydrate, leaves the most important for nitrogen. Over 50 per cent of the nitrogen in the stem and leaves was redistributed. Plants that received 6 mM nitrate accumulated more dry matter than urea-grown plants. Seeds from nitrate-grown plants were heavier (58 mg) than those of urea-grown plants (46 mg), and their percentage oil was greater (50 and 41 respectively). The amount of nitrogen per seed was the same. Little or no urea was detected in xylem sap of plants supplied with 5 mM urea, but it was detected in sap of plants which received 25 mM. Concentrations of urea and amino compounds in the sap decreased up the stem. Plants supplied with nitrate had most of the nitrogen in xylem sap as NO2−, suggesting little nitrate reduction in roots. Plants grown on 6 mM nitrate and changed to high levels of urea-nitrogen for 14 days still had high levels of nitrate; little nitrate remained in plants receiving low levels of urea. When urea is applied in irrigation water to field-grown sunflower, the nitrogen is subsequently taken up as nitrate due to rapid nitrogen transformations in the soil.
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Claims 20
Claim · model-written summary
Seed dry matter was transferred to seedlings with a net efficiency of 40 per cent.
- Taxon
- Helianthus annuus
Helianthus annuuse0 - Material
- Hysun 21e0
- Outcome
- Seed dry mattere1
- Value
- 40e1
- Qualifier
- net efficienciese1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Helianthus annuus L. cv. Hysun 21 grown on 6 mM urea in glasshouse culture”
e1“Seed dry matter and nitrogen were transferred to seedlings with net efficiencies of 40 and 86 per cent respectively”
Claim · model-written summary
Seed nitrogen was transferred to seedlings with a net efficiency of 86 per cent.
- Taxon
- Helianthus annuusHelianthus annuuse0
- Material
- Hysun 21e0
- Outcome
- nitrogene1
- Value
- 86 per cente1
- Qualifier
- net efficienciese1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Helianthus annuus L. cv. Hysun 21 grown on 6 mM urea in glasshouse culture”
e1“Seed dry matter and nitrogen were transferred to seedlings with net efficiencies of 40 and 86 per cent respectively”
Claim · model-written summary
At flowering the stem held most of the plant's dry matter.
- Taxon
- Helianthus annuusHelianthus annuuse0
- Material
- Hysun 21e0
- Organ / stage
- steme1
- Outcome
- most of the plant's dry mattere1
- Qualifier
- At floweringe1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Helianthus annuus L. cv. Hysun 21 grown on 6 mM urea in glasshouse culture”
e1“At flowering, the stem had most of the plant's dry matter and the leaves most of its nitrogen”
Claim · model-written summary
At flowering the leaves held most of the plant's nitrogen.
- Taxon
- Helianthus annuusHelianthus annuuse0
- Material
- Hysun 21e0
- Organ / stage
- leavese1
- Outcome
- most of its nitrogene1
- Qualifier
- At floweringe1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Helianthus annuus L. cv. Hysun 21 grown on 6 mM urea in glasshouse culture”
e1“At flowering, the stem had most of the plant's dry matter and the leaves most of its nitrogen”
Claim · model-written summary
About 35 per cent of the plant's nitrogen accumulated after three-row anthesis.
- Taxon
- Helianthus annuusHelianthus annuuse0
- Material
- Hysun 21e0
- Outcome
- the plant's nitrogene1
- Value
- About 35 per cente1
- Qualifier
- after three-row anthesise1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Helianthus annuus L. cv. Hysun 21 grown on 6 mM urea in glasshouse culture”
e1“About 35 per cent of the plant's nitrogen accumulated after three-row anthesis”
Claim · model-written summary
The amount of protein in vegetative parts, especially leaves, declined after flowering.
- Taxon
- Helianthus annuusHelianthus annuuse0
- Material
- Hysun 21e0
- Organ / stage
- vegetative partse1
- Outcome
- amount of proteine1
- Direction
- declinede1
- Qualifier
- after floweringe1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Helianthus annuus L. cv. Hysun 21 grown on 6 mM urea in glasshouse culture”
e1“The amount of protein in vegetative parts, especially leaves, declined after flowering”
Claim · model-written summary
Concentrations of free amino compounds decreased during growth.
- Taxon
- Helianthus annuusHelianthus annuuse0
- Material
- Hysun 21e0
- Outcome
- Concentrations of free amino compoundse1
- Direction
- decreasede1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Helianthus annuus L. cv. Hysun 21 grown on 6 mM urea in glasshouse culture”
e1“Concentrations of free amino compounds also decreased during growth”
Claim · model-written summary
Mature seeds held 38 per cent of the total plant dry weight.
- Taxon
- Helianthus annuusHelianthus annuuse0
- Material
- Hysun 21e0
- Organ / stage
- Mature seedse1
- Outcome
- total plant dry weighte1
- Value
- 38 per cente1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Helianthus annuus L. cv. Hysun 21 grown on 6 mM urea in glasshouse culture”
e1“Mature seeds had 38 per cent of the total plant dry weight and 68 per cent of the total nitrogen”
Claim · model-written summary
Mature seeds held 68 per cent of the total plant nitrogen.
- Taxon
- Helianthus annuusHelianthus annuuse0
- Material
- Hysun 21e0
- Organ / stage
- Mature seedse1
- Outcome
- total nitrogene1
- Value
- 68 per cente1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Helianthus annuus L. cv. Hysun 21 grown on 6 mM urea in glasshouse culture”
e1“Mature seeds had 38 per cent of the total plant dry weight and 68 per cent of the total nitrogen”
Claim · model-written summary
Seeds acquired 33 per cent of their dry matter and nitrogen by redistribution from above-ground plant parts.
- Taxon
- Helianthus annuusHelianthus annuuse0
- Material
- Hysun 21e0
- Organ / stage
- Seedse1
- Outcome
- dry matter and nitrogene1
- Value
- 33 per cente1
- Qualifier
- redistribution from above-ground plant partse1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Helianthus annuus L. cv. Hysun 21 grown on 6 mM urea in glasshouse culture”
e1“Seeds acquired 33 per cent of their dry matter and nitrogen from redistribution from above-ground plant parts”
Claim · model-written summary
Over 50 per cent of the nitrogen in the stem and leaves was redistributed.
- Taxon
- Helianthus annuusHelianthus annuuse0
- Material
- Hysun 21e0
- Organ / stage
- stem and leavese1
- Outcome
- nitrogene1
- Value
- Over 50 per cente1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Helianthus annuus L. cv. Hysun 21 grown on 6 mM urea in glasshouse culture”
e1“Over 50 per cent of the nitrogen in the stem and leaves was redistributed”
Claim · model-written summary
Sunflower plants receiving 6 mM nitrate accumulated more dry matter than urea-grown plants.
- Taxon
- Helianthus annuusHelianthus annuuse0
- Material
- Hysun 21e0
- Treatment
- 6 mM nitratee1
- Outcome
- dry mattere1
- Direction
- moree1
- Comparator
- urea-grown plantse1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Helianthus annuus L. cv. Hysun 21 grown on 6 mM urea in glasshouse culture”
e1“Plants that received 6 mM nitrate accumulated more dry matter than urea-grown plants”
Claim · model-written summary
Seeds from nitrate-grown plants were heavier (58 mg) than those of urea-grown plants (46 mg).
- Taxon
- Helianthus annuusHelianthus annuuse0
- Material
- Hysun 21e0
- Treatment
- nitrate-grown plantse1
- Outcome
- Seedse1
- Direction
- heaviere1
- Value
- 58 mge1
- Qualifier
- 46 mge1
- Comparator
- urea-grown plantse1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Helianthus annuus L. cv. Hysun 21 grown on 6 mM urea in glasshouse culture”
e1“Seeds from nitrate-grown plants were heavier (58 mg) than those of urea-grown plants (46 mg)”
Claim · model-written summary
Seeds from nitrate-grown plants had a greater oil percentage (50) than those from urea-grown plants (41).
- Taxon
- Helianthus annuusHelianthus annuuse0
- Material
- Hysun 21e0
- Treatment
- nitrate-grown plantse1
- Outcome
- percentage oile2
- Direction
- greatere2
- Value
- 50e2
- Qualifier
- 41e2
- Comparator
- urea-grown plantse1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Helianthus annuus L. cv. Hysun 21 grown on 6 mM urea in glasshouse culture”
e1“Seeds from nitrate-grown plants were heavier (58 mg) than those of urea-grown plants (46 mg)”
e2“their percentage oil was greater (50 and 41 respectively)”
Claim · model-written summary
The amount of nitrogen per seed was the same for nitrate-grown and urea-grown plants.
- Taxon
- Helianthus annuusHelianthus annuuse0
- Material
- Hysun 21e0
- Treatment
- nitrate-grown plantse1
- Outcome
- amount of nitrogen per seede2
- Direction
- the samee2
- Comparator
- urea-grown plantse1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Helianthus annuus L. cv. Hysun 21 grown on 6 mM urea in glasshouse culture”
e1“Seeds from nitrate-grown plants were heavier (58 mg) than those of urea-grown plants (46 mg)”
e2“The amount of nitrogen per seed was the same”
Claim · model-written summary
Little or no urea was detected in xylem sap of plants supplied with 5 mM urea, but it was detected at 25 mM.
- Taxon
- Helianthus annuusHelianthus annuuse0
- Material
- Hysun 21e0
- Outcome
- Little or no urea was detected in xylem sape1
- Qualifier
- but it was detected in sap of plants which received 25 mMe1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Helianthus annuus L. cv. Hysun 21 grown on 6 mM urea in glasshouse culture”
e1“Little or no urea was detected in xylem sap of plants supplied with 5 mM urea, but it was detected in sap of plants which received 25 mM”
Claim · model-written summary
Concentrations of urea and amino compounds in the xylem sap decreased up the stem.
- Taxon
- Helianthus annuusHelianthus annuuse0
- Material
- Hysun 21e0
- Outcome
- Concentrations of urea and amino compounds in the sape1
- Direction
- decreasede1
- Qualifier
- up the steme1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Helianthus annuus L. cv. Hysun 21 grown on 6 mM urea in glasshouse culture”
e1“Concentrations of urea and amino compounds in the sap decreased up the stem”
Claim · model-written summary
In nitrate-supplied plants most xylem sap nitrogen was NO2−, suggesting little nitrate reduction in roots.
- Taxon
- Helianthus annuusHelianthus annuuse0
- Material
- Hysun 21e0
- Outcome
- most of the nitrogen in xylem sap as NO2−e1
- Qualifier
- suggesting little nitrate reduction in rootse1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Helianthus annuus L. cv. Hysun 21 grown on 6 mM urea in glasshouse culture”
e1“Plants supplied with nitrate had most of the nitrogen in xylem sap as NO2−, suggesting little nitrate reduction in roots”
Claim · model-written summary
Plants grown on 6 mM nitrate and changed to high urea-nitrogen for 14 days still had high nitrate, while little nitrate remained in plants receiving low urea.
- Taxon
- Helianthus annuusHelianthus annuuse0
- Material
- Hysun 21e0
- Outcome
- high levels of nitratee1
- Qualifier
- little nitrate remained in plants receiving low levels of ureae1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Helianthus annuus L. cv. Hysun 21 grown on 6 mM urea in glasshouse culture”
e1“Plants grown on 6 mM nitrate and changed to high levels of urea-nitrogen for 14 days still had high levels of nitrate; little nitrate remained in plants receiving low levels of urea”
Claim · model-written summary
The authors conclude that urea applied in irrigation water to field-grown sunflower is subsequently taken up as nitrate because of rapid soil nitrogen transformations.
- Taxon
- sunflowerHelianthus annuuse0
- Treatment
- urea is applied in irrigation watere0
- Outcome
- the nitrogen is subsequently taken up as nitratee0
- Qualifier
- rapid nitrogen transformations in the soile0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“When urea is applied in irrigation water to field-grown sunflower, the nitrogen is subsequently taken up as nitrate due to rapid nitrogen transformations in the soil”
The same questions in other papers
nitrogen · growth · Helianthus annuus (common sunflower)Results differ
62 papers in the same direction as this paper · 12 in the opposite direction · 1 reporting no difference from an alternative
- no effect
- negative
- negative
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See all 76 papers →nitrogen · yield · Helianthus annuus (common sunflower)Positive and negative results
181 papers in the same direction as this paper · 10 in the opposite direction · 4 reporting no difference from an alternative
- negative
- no effect
- negative
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See all 196 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.