Abstract
Early seedling growth and glutamine synthetase and glutamate dehydrogenase activities of the normal and opague-2 (o2) genotypes of maize were compared in the presence or absence of added N. In the absence of exogenous N, the dry weight of o2 seedlings was only 60% of the dry weight of normal seedlings at 21 days after germination; however, the dry weights were comparable when exogenous N, especially as NO − 3 , was supplied to both genotypes. Thus, exogenous N appears to be more critical for early growth of o2 than normal seedlings. Growth of o2 seedlings was more severely restricted than of the normal genotype by high concentrations of NH + 4 . A combination of NH + 4 and NO − 3 resulted in better growth of both genotypes than either form on N alone. There was no difference in the capacity of the two genotypes to accumulate N from exogenous NH + 4 or NO − 3 . However, both genotypes accumulated relatively more N from NH + 4 than from NO − 3 . Glutamine synthetase activity in o2 roots was twofold higher than in the normal genotype in the absence of exogenous N but was similar in the roots of both gentoypes when seedlings were grown in either NO − 3 or NH + 4 . In the absence of exogenous N, glutamate dehydrogenase activity in o2 roots was 2.8-fold higher than in normal roots and remained higher when NH + 4 was added.Key words: Nitrogen form, ammonium, nitrate, glutamate dehydrogenase, glutamine synthetase, zein
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 10
Claim · model-written summary
Without exogenous N, o2 seedlings had 60% of normal seedling dry weight at 21 days.
- Material
- o2e0
- Outcome
- dry weight of o2 seedlingse0
- Value
- 60%e0
- Qualifier
- 21 days after germinatione0
- Comparator
- normal seedlingse0
Zea maysOrganisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“In the absence of exogenous N, the dry weight of o2 seedlings was only 60% of the dry weight of normal seedlings at 21 days after germination”
t0“MAIZE”
Claim · model-written summary
Added nitrogen made dry weights comparable across genotypes, especially as nitrate.
- Treatment
- exogenous Ne0
- Outcome
- dry weightse0
- Direction
- comparablee0
- Qualifier
- especially as NO − 3e0
- Comparator
- both genotypese0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the dry weights were comparable when exogenous N, especially as NO − 3 , was supplied to both genotypes”
t0“MAIZE”
Claim · model-written summary
High ammonium restricted o2 growth more severely than normal genotype growth.
- Material
- o2e0
- Treatment
- high concentrations of NH + 4e0
- Outcome
- Growth of o2 seedlingse0
- Direction
- more severely restrictede0
- Comparator
- normal genotypee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Growth of o2 seedlings was more severely restricted than of the normal genotype by high concentrations of NH + 4”
t0“MAIZE”
Claim · model-written summary
Combined ammonium and nitrate improved growth relative to either alone.
- Treatment
- combination of NH + 4 and NO − 3e0
- Outcome
- growth of both genotypese0
- Direction
- bettere0
- Comparator
- either form on N alonee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“A combination of NH + 4 and NO − 3 resulted in better growth of both genotypes than either form on N alone”
t0“MAIZE”
Claim · model-written summary
Genotypes did not differ in capacity to accumulate external nitrogen.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“There was no difference in the capacity of the two genotypes to accumulate N from exogenous NH + 4 or NO − 3”
t0“MAIZE”
Claim · model-written summary
Both genotypes accumulated more nitrogen from ammonium than nitrate.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“both genotypes accumulated relatively more N from NH + 4 than from NO − 3”
t0“MAIZE”
Claim · model-written summary
Without external N, root glutamine synthetase activity was twice as high in o2.
- Material
- o2e0
- Organ / stage
- rootse0
- Gene
- Glutamine synthetasee0
- Outcome
- Glutamine synthetase activitye0
- Direction
- highere0
- Value
- twofolde0
- Comparator
- normal genotypee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Glutamine synthetase activity in o2 roots was twofold higher than in the normal genotype in the absence of exogenous N”
t0“MAIZE”
Claim · model-written summary
With nitrate or ammonium, root glutamine synthetase activity was similar between genotypes.
- Organ / stage
- rootse0
- Treatment
- either NO − 3 or NH + 4e0
- Gene
- Glutamine synthetasee1
- Outcome
- similar in the roots of both gentoypese0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“was similar in the roots of both gentoypes when seedlings were grown in either NO − 3 or NH + 4”
t0“MAIZE”
e1“Glutamine synthetase activity in o2 roots was twofold higher than in the normal genotype in the absence of exogenous N”
Claim · model-written summary
Without external N, root glutamate dehydrogenase activity was 2.8-fold higher in o2.
- Material
- o2e0
- Organ / stage
- rootse0
- Gene
- glutamate dehydrogenasee0
- Outcome
- glutamate dehydrogenase activitye0
- Direction
- highere0
- Value
- 2.8-folde0
- Comparator
- normal rootse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“In the absence of exogenous N, glutamate dehydrogenase activity in o2 roots was 2.8-fold higher than in normal roots”
t0“MAIZE”
Claim · model-written summary
Root glutamate dehydrogenase activity remained higher in o2 with ammonium added.
- Material
- o2e1
- Treatment
- NH + 4e0
- Gene
- glutamate dehydrogenasee1
- Outcome
- glutamate dehydrogenase activitye1
- Direction
- highere0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“remained higher when NH + 4 was added”
t0“MAIZE”
e1“In the absence of exogenous N, glutamate dehydrogenase activity in o2 roots was 2.8-fold higher than in normal roots”
The same questions in other papers
nitric oxide · growth · Zea mays (maize)Positive and negative results
7 papers in the same direction as this paper · 5 in the opposite direction
- negative
- no effect
- negative
9 papers more in this group
See all 13 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.