Abstract
The effects of ammonium-nitrogen (NH4+-N) to nitrate nitrogen (NO3--N) ratios (0∶100, 25∶75, 50∶50, 75∶25, 100∶0) in the nutrient solution on ascorbate (AsA) contents and its related metabolic enzyme activities in hydroponically grown spinach (Spinacia oleracea L.) were studied. Results show that both fresh and dry weights were significantly decreased when NH4+-N to NO3--N ratio exceeded 50∶50, and highest fresh and dry weight was recorded at the NH4+-N to NO3--N ratio of 25∶75. AsA and (AsA + DHA) contents increased gradually, while the ratios of AsA/(AsA + DHA) had no significant change with increasing of NH4+-N to NO3--N ratio. The enzymes activities of L-galactono-1,4-lactone dehydrogenase (GalLDH) were not decreased until the ratio of NH4+-N to NO3--N was over 50∶50 and the ascorbate oxidase (AAO) had no significant change with increasing NH4+-N ratio. The ascorbate peroxidase (APX) activity was decreased firstly and then increased when the NH4+-N ratio was elevated. The activities of two enzymes related to AsA regeneration, the dehydroascorbate reductase (DHAR) and monodehydroascorbate reductase (MDHAR) increased as well as the trends of ascorbate content when elevated NH4+-N∶NO3--N ratio. The results suggested that AsA contents increased with increasing NH4+-N to NO3--N ratio in the nutrient solution could be attributed to the enhanced DHAR and MDHAR activities in AsA metabolism, could not be significantly related to the changes of GalLDH and AAO activities.
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Claims 10
Claim · model-written summary
Fresh and dry weights of spinach were significantly decreased when the NH4+-N to NO3--N ratio exceeded 50:50.
- Taxon
- Spinacia oleracea L.
Spinacia oleraceae1 - Treatment
- ammonium-nitrogen (NH4+-N) to nitrate nitrogen (NO3--N) ratiose0
- Outcome
- fresh and dry weightse2
- Direction
- decreasede2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The effects of ammonium-nitrogen (NH4+-N) to nitrate nitrogen (NO3--N) ratios”
e1“hydroponically grown spinach (Spinacia oleracea L.)”
e2“both fresh and dry weights were significantly decreased when NH4+-N to NO3--N ratio exceeded 50∶50”
Claim · model-written summary
Spinach had the highest fresh and dry weight at an NH4+-N to NO3--N ratio of 25:75.
- Taxon
- Spinacia oleracea L.Spinacia oleraceae1
- Treatment
- ammonium-nitrogen (NH4+-N) to nitrate nitrogen (NO3--N) ratiose0
- Outcome
- fresh and dry weighte2
- Direction
- higheste2
- Qualifier
- 25∶75e2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The effects of ammonium-nitrogen (NH4+-N) to nitrate nitrogen (NO3--N) ratios”
e1“hydroponically grown spinach (Spinacia oleracea L.)”
e2“highest fresh and dry weight was recorded at the NH4+-N to NO3--N ratio of 25∶75”
Claim · model-written summary
AsA and AsA+DHA contents of spinach increased gradually with increasing NH4+-N to NO3--N ratio.
- Taxon
- Spinacia oleracea L.Spinacia oleraceae1
- Treatment
- ammonium-nitrogen (NH4+-N) to nitrate nitrogen (NO3--N) ratiose0
- Outcome
- AsA and (AsA + DHA) contentse2
- Direction
- increased graduallye2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The effects of ammonium-nitrogen (NH4+-N) to nitrate nitrogen (NO3--N) ratios”
e1“hydroponically grown spinach (Spinacia oleracea L.)”
e2“AsA and (AsA + DHA) contents increased gradually”
Claim · model-written summary
The AsA/(AsA+DHA) ratio of spinach showed no significant change with increasing NH4+-N to NO3--N ratio.
- Taxon
- Spinacia oleracea L.Spinacia oleraceae1
- Treatment
- ammonium-nitrogen (NH4+-N) to nitrate nitrogen (NO3--N) ratiose0
- Outcome
- ratios of AsA/(AsA + DHA)e2
- Direction
- no significant changee2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The effects of ammonium-nitrogen (NH4+-N) to nitrate nitrogen (NO3--N) ratios”
e1“hydroponically grown spinach (Spinacia oleracea L.)”
e2“the ratios of AsA/(AsA + DHA) had no significant change”
Claim · model-written summary
GalLDH activity in spinach was not decreased until the NH4+-N to NO3--N ratio exceeded 50:50.
- Taxon
- Spinacia oleracea L.Spinacia oleraceae1
- Treatment
- ammonium-nitrogen (NH4+-N) to nitrate nitrogen (NO3--N) ratiose0
- Gene
- L-galactono-1,4-lactone dehydrogenase (GalLDH)e2
- Outcome
- enzymes activities of L-galactono-1,4-lactone dehydrogenase (GalLDH)e2
- Direction
- not decreasede2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The effects of ammonium-nitrogen (NH4+-N) to nitrate nitrogen (NO3--N) ratios”
e1“hydroponically grown spinach (Spinacia oleracea L.)”
e2“The enzymes activities of L-galactono-1,4-lactone dehydrogenase (GalLDH) were not decreased until the ratio of NH4+-N to NO3--N was over 50∶50”
Claim · model-written summary
Ascorbate oxidase (AAO) activity in spinach showed no significant change with increasing NH4+-N ratio.
- Taxon
- Spinacia oleracea L.Spinacia oleraceae1
- Treatment
- ammonium-nitrogen (NH4+-N) to nitrate nitrogen (NO3--N) ratiose0
- Outcome
- the ascorbate oxidase (AAO)e2
- Direction
- no significant changee2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The effects of ammonium-nitrogen (NH4+-N) to nitrate nitrogen (NO3--N) ratios”
e1“hydroponically grown spinach (Spinacia oleracea L.)”
e2“the ascorbate oxidase (AAO) had no significant change”
Claim · model-written summary
Ascorbate peroxidase (APX) activity in spinach first decreased and then increased as the NH4+-N ratio rose.
- Taxon
- Spinacia oleracea L.Spinacia oleraceae1
- Treatment
- ammonium-nitrogen (NH4+-N) to nitrate nitrogen (NO3--N) ratiose0
- Gene
- ascorbate peroxidase (APX)e2
- Outcome
- ascorbate peroxidase (APX) activitye2
- Direction
- decreased firstly and then increasede2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The effects of ammonium-nitrogen (NH4+-N) to nitrate nitrogen (NO3--N) ratios”
e1“hydroponically grown spinach (Spinacia oleracea L.)”
e2“The ascorbate peroxidase (APX) activity was decreased firstly and then increased”
Claim · model-written summary
The activities of DHAR and MDHAR in spinach increased with elevated NH4+-N to NO3--N ratio.
- Taxon
- Spinacia oleracea L.Spinacia oleraceae1
- Treatment
- ammonium-nitrogen (NH4+-N) to nitrate nitrogen (NO3--N) ratiose0
- Gene
- dehydroascorbate reductase (DHAR) and monodehydroascorbate reductase (MDHAR)e2
- Outcome
- activities of two enzymes related to AsA regeneratione2
- Direction
- increasede2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The effects of ammonium-nitrogen (NH4+-N) to nitrate nitrogen (NO3--N) ratios”
e1“hydroponically grown spinach (Spinacia oleracea L.)”
e2“The activities of two enzymes related to AsA regeneration, the dehydroascorbate reductase (DHAR) and monodehydroascorbate reductase (MDHAR) increased”
Claim · model-written summary
The increase of AsA contents with rising NH4+-N to NO3--N ratio could be attributed to enhanced DHAR and MDHAR activities.
- Taxon
- Spinacia oleracea L.Spinacia oleraceae1
- Gene
- DHAR and MDHARe2
- Outcome
- AsA contentse2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The effects of ammonium-nitrogen (NH4+-N) to nitrate nitrogen (NO3--N) ratios”
e1“hydroponically grown spinach (Spinacia oleracea L.)”
e2“The results suggested that AsA contents increased with increasing NH4+-N to NO3--N ratio in the nutrient solution could be attributed to the enhanced DHAR and MDHAR activities in AsA metabolism, could not be significantly related to the changes of GalLDH and AAO activities”
Claim · model-written summary
Changes in GalLDH and AAO activities could not be significantly related to AsA contents in spinach.
- Taxon
- Spinacia oleracea L.Spinacia oleraceae1
- Gene
- GalLDH and AAOe2
- Outcome
- AsA contentse2
- Direction
- could not be significantly relatede2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The effects of ammonium-nitrogen (NH4+-N) to nitrate nitrogen (NO3--N) ratios”
e1“hydroponically grown spinach (Spinacia oleracea L.)”
e2“The results suggested that AsA contents increased with increasing NH4+-N to NO3--N ratio in the nutrient solution could be attributed to the enhanced DHAR and MDHAR activities in AsA metabolism, could not be significantly related to the changes of GalLDH and AAO activities”
The same questions in other papers
nitrogen · molecular: metabolites · Spinacia oleracea (spinach)Positive and negative results
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