Abstract
Putrescine (Put), spermidine (Spd), and spermine (Spm) are the major polyamines (PAs) in plant, which are not only involved in the regulation of plant developmental and physiological processes, but also play key roles in modulating the defense response of plants to diverse environmental stresses. In this study, Cucumis sativus L. seedlings were cultivated in nutrient solution and sprayed with three kinds of PAs (Put, Spd, and Spm). The effects of PAs were investigated on excess nitrate stress tolerance of C. sativus by measuring growth and nitrogen (N) metabolism parameters. The contents of NO 3- − N, NH 4- + N, proline and soluble protein in leaves were increased; while plant height, leaf area, shoot fresh and dry weight, root fresh weight were decreased under 140 mM NO 3 − treatment for 7 d. In addition, the activities of nitrate reductase (NR), glutamate synthase (GOGAT), and glutamate dehydrogenase (GDH) were significantly inhibited under 140 mM NO 3 − treatment for 7 d. With foliar treatment by 1 mM Spd or Spm under stress treatment, the contents of Spm, Put, and Spd in leaves increased significantly, except that Spm content decreased under Spd treatment. The activities of NR, glutamine synthetase (GS), GOGAT and GDH and plant height, leaf area, shoot fresh and dry weights were significantly increased. The contents of proline and soluble protein in leaves were significantly enhanced. In contrast, the accumulation of NO 3- − N and NH 4- + N were significantly decreased. However, there were minor differences in activities of N metabolism enzymes and the content of osmotic adjustment substances under 1 mM Put treatment. These findings suggest that 1 mM exogenous Spm or Spd could enhance the capacity of N metabolism, promote growth and increase resistance to high concentrations of NO 3 − . The ameliorating effect of Spd was the best, and that of Put the worst.
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Claims 10
Claim · model-written summary
Excess nitrate reduced height, leaf area and shoot and root mass.
- Taxon
- Cucumis sativus L.
Cucumis sativuse1 - Treatment
- 140 mM NO 3 − treatment for 7 de0
- Outcome
- plant height, leaf area, shoot fresh and dry weight, root fresh weighte0
- Direction
- decreasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“plant height, leaf area, shoot fresh and dry weight, root fresh weight were decreased under 140 mM NO 3 − treatment for 7 d”
e1“Cucumis sativus L. seedlings”
Claim · model-written summary
Excess nitrate significantly inhibited NR, GOGAT and GDH activities.
- Taxon
- Cucumis sativus L.Cucumis sativuse1
- Treatment
- 140 mM NO 3 − treatment for 7 de0
- Outcome
- activities of nitrate reductase (NR), glutamate synthase (GOGAT), and glutamate dehydrogenase (GDH)e0
- Direction
- inhibitede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“activities of nitrate reductase (NR), glutamate synthase (GOGAT), and glutamate dehydrogenase (GDH) were significantly inhibited under 140 mM NO 3 − treatment for 7 d”
e1“Cucumis sativus L. seedlings”
Claim · model-written summary
Under nitrate stress, spermidine increased leaf Spm, Put and Spd except that Spm itself decreased under Spd treatment.
- Taxon
- Cucumis sativus L.Cucumis sativuse1
- Treatment
- 1 mM Spde0
- Outcome
- contents of Spm, Put, and Spd in leavese0
Not reportedComparatorDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“With foliar treatment by 1 mM Spd or Spm under stress treatment, the contents of Spm, Put, and Spd in leaves increased significantly, except that Spm content decreased under Spd treatment”
e1“Cucumis sativus L. seedlings”
Claim · model-written summary
Under nitrate stress, spermine increased leaf polyamine contents.
- Taxon
- Cucumis sativus L.Cucumis sativuse1
- Treatment
- Spme0
- Outcome
- contents of Spm, Put, and Spd in leavese0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“With foliar treatment by 1 mM Spd or Spm under stress treatment, the contents of Spm, Put, and Spd in leaves increased significantly”
e1“Cucumis sativus L. seedlings”
Claim · model-written summary
Spermidine raised nitrogen metabolism enzyme activities and growth traits under nitrate stress.
- Taxon
- Cucumis sativus L.Cucumis sativuse1
- Treatment
- 1 mM Spde2
- Outcome
- activities of NR, glutamine synthetase (GS), GOGAT and GDHe0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The activities of NR, glutamine synthetase (GS), GOGAT and GDH and plant height, leaf area, shoot fresh and dry weights were significantly increased”
e1“Cucumis sativus L. seedlings”
e2“1 mM Spd or Spm”
Claim · model-written summary
Spermine raised nitrogen metabolism enzyme activities and growth traits under nitrate stress.
- Taxon
- Cucumis sativus L.Cucumis sativuse1
- Treatment
- Spme2
- Outcome
- plant height, leaf area, shoot fresh and dry weightse0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The activities of NR, glutamine synthetase (GS), GOGAT and GDH and plant height, leaf area, shoot fresh and dry weights were significantly increased”
e1“Cucumis sativus L. seedlings”
e2“1 mM Spd or Spm”
Claim · model-written summary
Spermidine and spermine increased leaf proline and soluble protein under nitrate stress.
- Taxon
- Cucumis sativus L.Cucumis sativuse1
- Treatment
- 1 mM Spd or Spme2
- Outcome
- contents of proline and soluble protein in leavese0
- Direction
- enhancede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The contents of proline and soluble protein in leaves were significantly enhanced”
e1“Cucumis sativus L. seedlings”
e2“1 mM Spd or Spm”
Claim · model-written summary
Spermidine and spermine reduced nitrate and ammonium accumulation under nitrate stress.
- Taxon
- Cucumis sativus L.Cucumis sativuse1
- Treatment
- 1 mM Spd or Spme2
- Outcome
- accumulation of NO 3- − N and NH 4- + Ne0
- Direction
- decreasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the accumulation of NO 3- − N and NH 4- + N were significantly decreased”
e1“Cucumis sativus L. seedlings”
e2“1 mM Spd or Spm”
Claim · model-written summary
Putrescine caused only minor differences in nitrogen metabolism enzymes and osmotic substances.
- Taxon
- Cucumis sativus L.Cucumis sativuse1
- Treatment
- 1 mM Put treatmente0
- Outcome
- minor differences in activities of N metabolism enzymes and the content of osmotic adjustment substancese0
Not reportedComparatorDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“there were minor differences in activities of N metabolism enzymes and the content of osmotic adjustment substances under 1 mM Put treatment”
e1“Cucumis sativus L. seedlings”
Claim · model-written summary
The authors judged spermidine most effective and putrescine least effective for ameliorating nitrate stress.
- Taxon
- Cucumis sativus L.Cucumis sativuse1
- Outcome
- ameliorating effect of Spd was the best, and that of Put the worste0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The ameliorating effect of Spd was the best, and that of Put the worst”
e1“Cucumis sativus L. seedlings”
The same questions in other papers
spermine · physiology: osmolytes · Cucumis sativus (cucumber)Results agree
1 paper in the same direction as this paper
- positive
spermine · growth · Cucumis sativus (cucumber)Results agree
1 paper in the same direction as this paper
- positive
spermidine · physiology: osmolytes · Cucumis sativus (cucumber)Results agree
2 papers in the same direction as this paper
- positive
- positive
spermidine · physiology: enzyme activity · Cucumis sativus (cucumber)Results agree
3 papers in the same direction as this paper
- positive
- positive
- positive
spermidine · molecular: metabolites · Cucumis sativus (cucumber)Results agree
14 papers in the same direction as this paper
- positive
- positive
- positive
11 papers more in this group
See all 15 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.