Abstract
Abstract Background: Carbon (C) and nitrogen (N) assimilate availability and their ratios are crucial for maize grain production and N‐use efficiency. Aim: Our aim was to give a mechanistic understanding of yield formation regulated by assimilate C:N balance during both early ear development and rapid grain filling. Methods: Maize was grown under field conditions with 0, 200, and 300 kg N ha −1 (referred to as N0, N200, and N300, respectively). Ear growth, grain yield, and dynamics of total C and N accumulation in ear leaves, cobs, and developing kernels (apical and basal proportions separated from the longitudinally middle of ear) were investigated, as well as the non‐structural carbohydrates and free amino acids. Results: Compared to N‐sufficient plants, low‐N plants contained 16% to 70% less N and 8% to 50% less C in the developing kernels, causing 43% to 52% yield losses, which indicated that low‐N kernels received less amino acid per unit sugar from the maternal plants. This was supported by lower concentrations of the main N transport molecules (glutamine and asparagine) in ear leaves at silking and 21 days after silking (DAS) coupled with the larger amounts of C accumulated as starch under N deficient compared to adequate N supply. Nitrogen treatment did not influence the concentrations of total free amino acids and soluble protein in the cob, neither at silking nor 21 DAS, but it did influence cob free amino acid composition. Compared to the adequate N supply, low‐N plants contained 75% and 57% less glutamine and asparagine in apical kernels at silking, as well as 36% and 31% less in basal kernels. Free amino acid concentrations in both cob and kernels were less responsive to N treatments at 21 DAS than at silking, especially in the basal ear halves. Conclusion: Maize grain production under low‐N environment can be more attributed to the balance in assimilate composition, particularly the amino acid profile, than the C‐assimilate availability for ear growth and development.
Abstract from the paper’s OpenAlex record, shown for indexing and research. Copyright remains with the authors or the publisher. Read at the source ↗
The text the model read, with the source record’s inline markup (italics, sub- and superscripts) rendered and its character entities decoded; quote offsets refer to the raw text.
Claims 13
Claim · model-written summary
Low nitrogen reduced developing-kernel nitrogen 16% to 70%.
- Organ / stage
- developing kernelse0
- Treatment
- low‐Ne0
- Outcome
- Ne0
- Direction
- lesse0
- Value
- 16% to 70%e0
- Comparator
- N‐sufficiente1
Zea maysOrganisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“low‐N plants contained 16% to 70% less N and 8% to 50% less C in the developing kernels”
t0“low‐nitrogen maize”
e1“N‐sufficient plants”
Claim · model-written summary
Low nitrogen reduced developing-kernel carbon 8% to 50%.
- Treatment
- low‐Ne0
- Outcome
- C in the developing kernelse0
- Direction
- lesse0
- Value
- 8% to 50%e0
- Comparator
- N‐sufficiente1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“low‐N plants contained 16% to 70% less N and 8% to 50% less C in the developing kernels”
t0“low‐nitrogen maize”
e1“N‐sufficient plants”
Claim · model-written summary
Low nitrogen caused yield losses of 43% to 52%.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“causing 43% to 52% yield losses”
t0“low‐nitrogen maize”
e1“Compared to N‐sufficient plants, low‐N plants”
Claim · model-written summary
Glutamine and asparagine concentrations were lower in ear leaves.
- Organ / stage
- ear leavese0
- Treatment
- low‐Ne1
- Outcome
- concentrations of the main N transport molecules (glutamine and asparagine)e0
- Direction
- lowere0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“lower concentrations of the main N transport molecules (glutamine and asparagine) in ear leaves at silking and 21 days after silking (DAS)”
t0“low‐nitrogen maize”
e1“Compared to N‐sufficient plants, low‐N plants”
Claim · model-written summary
More carbon accumulated as starch under deficient nitrogen.
- Treatment
- N deficiente0
- Outcome
- C accumulated as starche0
- Direction
- largere0
- Comparator
- adequate N supplye0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“larger amounts of C accumulated as starch under N deficient compared to adequate N supply”
t0“low‐nitrogen maize”
Claim · model-written summary
Nitrogen treatment did not affect cob total free amino acid or soluble protein concentrations.
- Treatment
- Nitrogen treatmente0
- Outcome
- concentrations of total free amino acids and soluble protein in the cobe0
- Direction
- did not influencee0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Nitrogen treatment did not influence the concentrations of total free amino acids and soluble protein in the cob”
t0“low‐nitrogen maize”
Claim · model-written summary
Nitrogen treatment influenced cob free amino acid composition.
Not reportedComparatorDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“it did influence cob free amino acid composition”
t0“low‐nitrogen maize”
e1“Nitrogen treatment”
Claim · model-written summary
Low nitrogen reduced glutamine in apical kernels 75% at silking.
- Organ / stage
- apical kernelse0
- Treatment
- low‐Ne0
- Outcome
- glutaminee0
- Direction
- lesse0
- Value
- 75%e0
- Comparator
- adequate N supplye1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“low‐N plants contained 75% and 57% less glutamine and asparagine in apical kernels at silking”
t0“low‐nitrogen maize”
e1“Compared to the adequate N supply”
Claim · model-written summary
Low nitrogen reduced asparagine in apical kernels 57% at silking.
- Treatment
- low‐Ne0
- Outcome
- asparagine in apical kernelse0
- Direction
- lesse0
- Value
- 57%e0
- Comparator
- adequate N supplye1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“low‐N plants contained 75% and 57% less glutamine and asparagine in apical kernels at silking”
t0“low‐nitrogen maize”
e1“Compared to the adequate N supply”
Claim · model-written summary
Low nitrogen reduced glutamine in basal kernels 36%.
- Organ / stage
- basal kernelse0
- Treatment
- low‐Ne1
- Outcome
- glutaminee1
- Direction
- lesse0
- Value
- 36%e0
- Comparator
- adequate N supplye1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“as well as 36% and 31% less in basal kernels”
t0“low‐nitrogen maize”
e1“Compared to the adequate N supply, low‐N plants contained 75% and 57% less glutamine and asparagine in apical kernels at silking”
Claim · model-written summary
Low nitrogen reduced asparagine in basal kernels 31%.
- Organ / stage
- basal kernelse0
- Treatment
- low‐Ne1
- Outcome
- asparaginee1
- Direction
- lesse0
- Value
- 31%e0
- Comparator
- adequate N supplye1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“as well as 36% and 31% less in basal kernels”
t0“low‐nitrogen maize”
e1“Compared to the adequate N supply, low‐N plants contained 75% and 57% less glutamine and asparagine in apical kernels at silking”
Claim · model-written summary
Free amino acids in cob and kernels responded less to nitrogen at 21 DAS than silking.
- Treatment
- N treatmentse0
- Outcome
- Free amino acid concentrations in both cob and kernelse0
- Direction
- less responsivee0
- Comparator
- silkinge0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Free amino acid concentrations in both cob and kernels were less responsive to N treatments at 21 DAS than at silking, especially in the basal ear halves.”
t0“low‐nitrogen maize”
Claim · model-written summary
Authors attribute low-N grain production more to assimilate composition than carbon availability.
- Outcome
- grain production under low‐N environmente0
- Qualifier
- balance in assimilate composition, particularly the amino acid profilee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Maize grain production under low‐N environment can be more attributed to the balance in assimilate composition, particularly the amino acid profile, than the C‐assimilate availability for ear growth and development”
The same questions in other papers
nitrogen · physiology: osmolytes · Zea mays (maize)Positive and negative results
3 papers in the same direction as this paper · 15 in the opposite direction
- positive
- positive
- positive
15 papers more in this group
See all 19 papers →nitrogen · molecular: metabolites · Zea mays (maize)Positive and negative results
46 papers in the same direction as this paper · 95 in the opposite direction
- no effect
- no effect
- positive
138 papers more in this group
See all 142 papers →nitrogen · nutrient: content · Zea mays (maize)Positive and negative results
85 papers in the same direction as this paper · 403 in the opposite direction
- positive
- positive
- positive
485 papers more in this group
See all 489 papers →nitrogen · yield · Zea mays (maize)Positive and negative results
278 papers in the same direction as this paper · 1,906 in the opposite direction
- positive
- positive
- positive
2,181 papers more in this group
See all 2,185 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.