Abstract
Abstract Nitrogen (N) deficiency could have a negative effect on sunflower ( Helianthus annuus L.) yield and grain quality. Therefore, it is necessary to adjust the optimum rate, timing, and frequency of N fertilization to improve sunflower crop nutrition. Our objective was to evaluate the effect of N fertilization rate, timing, and splitting on grain yield, and grain and oil quality. Twelve field experiments were carried out between 2016 and 2020. Treatments consisted of at least three N rates ranging from 0 to 200 kg N ha −1 applied at V 2 . Moreover, the 80 kg N ha −1 rate was applied at V 14 (80N V14 ) or split between V 2 and V 14 (80N split ). Treatments were evaluated in two sunflower genotypes, high oleic (HO) and conventional (CONV). A significant grain yield response to N fertilization was observed in six out of twelve experiments, generally at rates greater than 80 kg ha −1 . The mean response to fertilization was 369 kg ha −1 . Fertilization increased grain protein concentration ( P G ) (+1.5%) at experiments E1–E3 and E9–E12 and decreased oil concentration ( O G ) (−2%) at experiments E1, E4, E9, E11, and E12. The maximum N rate, increased oleic and stearic acid concentration (+3%–4%), depending on the genotype (AO and CONV). Neither fertilizer timing nor splitting affected grain yield or O G . Late N fertilization (V 14 ) increased oleic acid (+2.4%), whereas it decreased linoleic acid (+2.2%). Based on our results, N fertilization can increase yield without negatively affecting commercial grain quality ( O G and fatty acids concentration), regardless of fertilization timing and frequency.
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Claims 10
Claim · model-written summary
N fertilization increased grain protein concentration by 1.5% in experiments E1–E3 and E9–E12.
- Taxon
- sunflower
Helianthus annuust0 - Treatment
- Fertilizatione0
- Outcome
- grain protein concentratione0
- Direction
- increasede0
- Value
- +1.5%e0
- Qualifier
- at experiments E1–E3 and E9–E12e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“sunflower yield and grain quality”
e0“Fertilization increased grain protein concentration ( P G ) (+1.5%) at experiments E1–E3 and E9–E12”
Claim · model-written summary
N fertilization decreased oil concentration by 2% in experiments E1, E4, E9, E11, and E12.
- Taxon
- sunflowerHelianthus annuust0
- Treatment
- Fertilizatione0
- Outcome
- oil concentratione1
- Direction
- decreasede1
- Value
- −2%e1
- Qualifier
- at experiments E1, E4, E9, E11, and E12e1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“sunflower yield and grain quality”
e0“Fertilization increased grain protein concentration ( P G ) (+1.5%) at experiments E1–E3 and E9–E12”
e1“decreased oil concentration ( O G ) (−2%) at experiments E1, E4, E9, E11, and E12”
Claim · model-written summary
N fertilization significantly increased grain yield in six of twelve experiments, generally at rates above 80 kg ha-1.
- Taxon
- sunflowerHelianthus annuust0
- Treatment
- N fertilizatione2
- Outcome
- grain yielde2
- Direction
- increaseinferrede2
- Qualifier
- in six out of twelve experiments, generally at rates greater than 80 kg ha −1e2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“sunflower yield and grain quality”
e2“A significant grain yield response to N fertilization was observed in six out of twelve experiments, generally at rates greater than 80 kg ha −1”
Claim · model-written summary
The mean grain yield response to N fertilization was 369 kg ha-1.
- Taxon
- sunflowerHelianthus annuust0
- Treatment
- fertilizatione3
- Outcome
- mean responsee3
- Direction
- increaseinferrede3
- Value
- 369 kg ha −1e3
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“sunflower yield and grain quality”
e3“The mean response to fertilization was 369 kg ha −1”
Claim · model-written summary
The maximum N rate increased oleic and stearic acid concentration by 3–4%, depending on genotype (AO and CONV).
- Taxon
- sunflowerHelianthus annuust0
- Material
- AO and CONVe4
- Treatment
- The maximum N ratee4
- Outcome
- oleic and stearic acid concentratione4
- Direction
- increasede4
- Value
- +3%–4%e4
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“sunflower yield and grain quality”
e4“The maximum N rate, increased oleic and stearic acid concentration (+3%–4%), depending on the genotype (AO and CONV)”
Claim · model-written summary
Fertilizer timing did not affect grain yield or oil concentration.
- Taxon
- sunflowerHelianthus annuust0
- Treatment
- fertilizer timinge5
- Outcome
- grain yield or O Ge5
- Direction
- no_changeinferrede5
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“sunflower yield and grain quality”
e5“Neither fertilizer timing nor splitting affected grain yield or O G”
Claim · model-written summary
Splitting the N fertilization did not affect grain yield or oil concentration.
- Taxon
- sunflowerHelianthus annuust0
- Treatment
- splittinge5
- Outcome
- grain yield or O Ge5
- Direction
- no_changeinferrede5
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“sunflower yield and grain quality”
e5“Neither fertilizer timing nor splitting affected grain yield or O G”
Claim · model-written summary
Late N fertilization increased oleic acid by 2.4%.
- Taxon
- sunflowerHelianthus annuust0
- Treatment
- Late N fertilizatione6
- Outcome
- oleic acide6
- Direction
- increasede6
- Value
- +2.4%e6
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“sunflower yield and grain quality”
e6“Late N fertilization (V 14) increased oleic acid (+2.4%), whereas it decreased linoleic acid (+2.2%)”
Claim · model-written summary
Late N fertilization decreased linoleic acid (reported as +2.2%).
- Taxon
- sunflowerHelianthus annuust0
- Treatment
- Late N fertilizatione6
- Outcome
- linoleic acide6
- Direction
- decreasede6
- Value
- +2.2%e6
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“sunflower yield and grain quality”
e6“Late N fertilization (V 14) increased oleic acid (+2.4%), whereas it decreased linoleic acid (+2.2%)”
Claim · model-written summary
N fertilization can increase sunflower yield without negatively affecting commercial grain quality, regardless of fertilization timing and frequency.
- Taxon
- sunflowerHelianthus annuust0
- Treatment
- N fertilizatione7
- Outcome
- yielde7
- Qualifier
- without negatively affecting commercial grain qualitye7
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“sunflower yield and grain quality”
e7“N fertilization can increase yield without negatively affecting commercial grain quality (O G and fatty acids concentration), regardless of fertilization timing and frequency”
The same questions in other papers
fertilization · quality: oil · Helianthus annuus (common sunflower)Results differ
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- positive
- no effect
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343 papers in the same direction as this paper · 18 in the opposite direction · 3 reporting no difference from an alternative
- no effect
- no effect
- no effect
361 papers more in this group
See all 365 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.