Abstract
This study was to elucidate the factors contributing to organic nitrogen (N) acquisition in different plant species, pak-choi (Brassica rapa L. var. chinensis) and tomato (Solanum lycopersicum L.). Two hypotheses were proposed and examined: 1) higher protease activity in rhizosphere contributes to the ability to utilize organic N in soils; 2) the differences in ability to absorb amino acids are responsible for the different characteristics of organic N utilization. Seedlings were grown in soils mixed with vermiculite with different N sources (no N (-N), ammonium sulfate (AS), and cattle farmyard manure (CM)). Plant growth and N accumulation were the best in the AS treatment in both species. When comparing the growth and N accumulation between -N and CM treatments, those of pak-choi were significantly enhanced in the CM treatment, but no difference was found in tomato. In the rhizosphere soils, the highest protease activities were detected in the CM treatment irrespective of plant species. The correlation analysis between rhizospheric protease activity and plant total N accumulation in the -N and CM treatments showed that a significant positive correlation only in pak-choi. The determination of amino acid absorption rate in excised roots indicated that glycine was taken up at significantly higher rate in pak-choi than in tomato. Taken together, two possible factors for the acquisition of organic N was suggested from this study: protease activity in rhizosphere and ability to absorb amino acids.
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 9
Claim · model-written summary
Ammonium sulfate gave the best plant growth and nitrogen accumulation in pak-choi.
Not reportedComparator
Verbatim
e0“Plant growth and N accumulation were the best in the AS treatment in both species.”
e1“pak-choi (Brassica rapa L. var. chinensis) and tomato (Solanum lycopersicum L.)”
e2“ammonium sulfate (AS)”
Claim · model-written summary
Ammonium sulfate gave the best plant growth and nitrogen accumulation in tomato.
- Taxon
- tomato
Solanum lycopersicume1 - Treatment
- AS treatmente0
- Outcome
- Plant growth and N accumulatione0
- Direction
- beste0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Plant growth and N accumulation were the best in the AS treatment in both species.”
e1“pak-choi (Brassica rapa L. var. chinensis) and tomato (Solanum lycopersicum L.)”
Claim · model-written summary
Manure significantly enhanced pak-choi growth and nitrogen accumulation relative to no nitrogen.
Verbatim
e0“When comparing the growth and N accumulation between -N and CM treatments, those of pak-choi were significantly enhanced in the CM treatment”
Claim · model-written summary
Tomato growth and nitrogen accumulation did not differ between manure and no nitrogen.
- Taxon
- tomatoSolanum lycopersicume0
- Treatment
- CM treatmentse0
- Outcome
- growth and N accumulatione0
- Direction
- no differencee0
- Comparator
- -Ne0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“When comparing the growth and N accumulation between -N and CM treatments, those of pak-choi were significantly enhanced in the CM treatment, but no difference was found in tomato.”
Claim · model-written summary
Rhizosphere protease activity was highest with manure in both species.
Not reportedComparator
Verbatim
e0“In the rhizosphere soils, the highest protease activities were detected in the CM treatment irrespective of plant species.”
e1“pak-choi (Brassica rapa L. var. chinensis) and tomato (Solanum lycopersicum L.)”
Claim · model-written summary
Rhizosphere protease activity was highest with manure in tomato.
- Taxon
- tomatoSolanum lycopersicume1
- Treatment
- CM treatmente0
- Outcome
- protease activitiese0
- Direction
- higheste0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“In the rhizosphere soils, the highest protease activities were detected in the CM treatment irrespective of plant species.”
e1“pak-choi (Brassica rapa L. var. chinensis) and tomato (Solanum lycopersicum L.)”
Claim · model-written summary
Rhizosphere protease activity correlated positively with total nitrogen accumulation only in pak-choi.
Verbatim
e0“a significant positive correlation only in pak-choi”
e1“The correlation analysis between rhizospheric protease activity and plant total N accumulation in the -N and CM treatments”
Claim · model-written summary
Excised pak-choi roots absorbed glycine significantly faster than tomato roots.
Verbatim
e0“glycine was taken up at significantly higher rate in pak-choi than in tomato”
e1“excised roots”
Claim · model-written summary
The authors propose rhizosphere protease activity and amino acid uptake capacity as two factors in organic nitrogen acquisition.
Verbatim
e0“two possible factors for the acquisition of organic N was suggested from this study: protease activity in rhizosphere and ability to absorb amino acids.”
e1“pak-choi (Brassica rapa L. var. chinensis) and tomato (Solanum lycopersicum L.)”
The same questions in other papers
ammonium sulfate · growth · Brassica rapa (field mustard)Positive and negative results
1 in the opposite direction
- negative
fertilization · physiology: enzyme activity · Solanum lycopersicum (tomato)Positive and negative results
8 papers in the same direction as this paper · 2 in the opposite direction
- negative
- no effect
- positive
7 papers more in this group
See all 11 papers →fertilization · growth · Brassica rapa (field mustard)Positive and negative results
106 papers in the same direction as this paper · 16 in the opposite direction · 4 reporting no difference from an alternative
- negative
- no effect
- no effect
123 papers more in this group
See all 127 papers →fertilization · growth · Solanum lycopersicum (tomato)Positive and negative results
100 papers in the same direction as this paper · 567 in the opposite direction
- positive
- positive
- positive
664 papers more in this group
See all 668 papers →fertilization · physiology: enzyme activity · Brassica rapa (field mustard)Results agree
2 papers in the same direction as this paper
- positive
- positive
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.