Paper · 2025 · Scientific Reports

Optimum concentrations of potassium and zinc for better performance, nutritional, and biochemical quality of hydroponically cultivated Spinacia oleracea Cv. Virofly

Farhad Behtash; Raana Ramezani; Hanifeh Seyed Hajizadeh; et al.

12
claims
22
verbatim quotes
4
citations
2
research areas
✓
Open access · cc-by-nc-nd

Abstract

In order to evaluate micro and macronutrient balance in vegetable growth, a study on greenness, yield, nutritional value, as well as biochemical status in spinach, has been conducted in a greenhouse, utilising the different concentrations of zinc (Zn) and potassium (K) in the nutrient solution. So, three concentrations of Zn (0.22, 5, and 10 mg L − 1 ) and K (39, 78, and 117 mg L − 1 ) were applied to hydroponically grown spinach ( Spinacia oleracea cv. Virofly) through a factorial experiment based on a randomized complete design with three replications. The results showed that along with increasing concentrations of Zn and K in a nutrient solution, chlorophyll index and plant performance were increased although Zn showed more influence than K. The maximum plant yield was observed at 117 mg L − 1 of K in combination with both concentrations of Zn (5 and 10 mg L − 1 ). Along with an increase in Zn and K concentrations, the amount of nutrients including Na, Fe, Cu, Ca, Mn, and Mg decreased compared to the control level of Zn and K in nutrient solution except for Zn and K, which increased due to the Zn and K, respectively. Increased levels of Zn and K caused to decrease in malondialdehyde (MDA) content by 51% and 34%, respectively. Hydrogen peroxide (H 2 O 2 ) was decreased also by 29% and 14% at 10 and 117 mg L − 1 concentration of Zn and K while higher levels of Zn and K in the nutrient solution, increased protein content by 1.4 and 1.2 folded compared to the control plants. The maximum activity of superoxide dismutase (SOD) was recorded in spinach treated with 10 mg L − 1 of Zn in combination independent to the K concentrations. The activity of ascorbate peroxidase (APX) was also affected by Zn as it showed up to 2.1 folded increment at 10 mg L − 1 Zn compared to the 0.22 mg L − 1 concentration. In general, an increase in Zn and K concentration in the nutrient solution decreased the absorption of measured nutrients except for Zn and K in spinach leaves. The effect of increased levels of Zn was more obvious than that of potassium in qualitative and biochemical traits of spinach specially at 5 mg L − 1 concentration. These findings suggest that supplementing hydroponic nutrient solutions with 5 mg L − 1 Zn in combination with 78 mg L − 1 K can lead to the better quality and tolerance of the plant, offering a promising strategy to enhance crop productivity and nutritional value in hydroponically cultivated spinach.

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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 12

Intervention effectobservedoriginal resultpositivemeasured

Claim · model-written summary

Increasing Zn and K raised chlorophyll index and plant performance.

Taxon
Spinacia oleraceaSpinacia oleraceat0
Treatment
increasing concentrations of Zn and Ke0
Outcome
chlorophyll index and plant performancee0
Direction
increasede0

Not reportedComparator

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Spinacia oleracea
Spinacia oleracea · TaxonRasbak · CC BY-SA 3.0 · Wikimedia Commons ↗

Verbatim

e0

“along with increasing concentrations of Zn and K in a nutrient solution, chlorophyll index and plant performance were increased”

✓ located verbatim in the source · abstract, characters 585–712 · show in text ↑
t0

“Spinacia oleracea”

✓ located verbatim in the source · title, characters 135–152 · show in text ↑
Observationobservedoriginal resultpositivemeasured

Claim · model-written summary

Yield was maximal at 117 mg L − 1 K with 5 or 10 mg L − 1 Zn.

Taxon
Spinacia oleraceaSpinacia oleraceat0
Treatment
117 mg L − 1 of Ke0
Outcome
maximum plant yielde0
Direction
maximume0
Qualifier
5 and 10 mg L − 1e0

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Spinacia oleracea
Spinacia oleracea · TaxonRasbak · CC BY-SA 3.0 · Wikimedia Commons ↗

Verbatim

e0

“The maximum plant yield was observed at 117 mg L − 1 of K in combination with both concentrations of Zn (5 and 10 mg L − 1 ).”

✓ located verbatim in the source · abstract, characters 755–880 · show in text ↑
t0

“Spinacia oleracea”

✓ located verbatim in the source · title, characters 135–152 · show in text ↑
Intervention effectobservedoriginal resultmixedmeasured

Claim · model-written summary

Higher Zn and K reduced Na, Fe, Cu, Ca, Mn and Mg nutrients.

Taxon
Spinacia oleraceaSpinacia oleraceat0
Treatment
increase in Zn and K concentrationse0
Outcome
Na, Fe, Cu, Ca, Mn, and Mge0
Direction
decreasede0
Comparator
control level of Zn and Ke0

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Spinacia oleracea
Spinacia oleracea · TaxonRasbak · CC BY-SA 3.0 · Wikimedia Commons ↗

Verbatim

e0

“Along with an increase in Zn and K concentrations, the amount of nutrients including Na, Fe, Cu, Ca, Mn, and Mg decreased compared to the control level of Zn and K in nutrient solution”

✓ located verbatim in the source · abstract, characters 881–1065 · show in text ↑
t0

“Spinacia oleracea”

✓ located verbatim in the source · title, characters 135–152 · show in text ↑
Intervention effectobservedoriginal resultpositivemeasured

Claim · model-written summary

Higher Zn reduced MDA by 51%.

Taxon
Spinacia oleraceaSpinacia oleraceat0
Treatment
Zne0
Outcome
malondialdehyde (MDA) contente0
Direction
decreasee0
Value
51%e0

Not reportedComparator

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Spinacia oleracea
Spinacia oleracea · TaxonRasbak · CC BY-SA 3.0 · Wikimedia Commons ↗

Verbatim

e0

“Increased levels of Zn and K caused to decrease in malondialdehyde (MDA) content by 51% and 34%, respectively.”

✓ located verbatim in the source · abstract, characters 1138–1248 · show in text ↑
t0

“Spinacia oleracea”

✓ located verbatim in the source · title, characters 135–152 · show in text ↑
Intervention effectobservedoriginal resultpositivemeasured

Claim · model-written summary

Higher K reduced MDA by 34%.

Taxon
Spinacia oleraceaSpinacia oleraceat0
Treatment
Ke0
Outcome
malondialdehyde (MDA) contente0
Direction
decreasee0
Value
34%e0

Not reportedComparator

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Spinacia oleracea
Spinacia oleracea · TaxonRasbak · CC BY-SA 3.0 · Wikimedia Commons ↗

Verbatim

e0

“Increased levels of Zn and K caused to decrease in malondialdehyde (MDA) content by 51% and 34%, respectively.”

✓ located verbatim in the source · abstract, characters 1138–1248 · show in text ↑
t0

“Spinacia oleracea”

✓ located verbatim in the source · title, characters 135–152 · show in text ↑
Intervention effectobservedoriginal resultpositivemeasured

Claim · model-written summary

Zn at 10 mg L − 1 decreased hydrogen peroxide 29%.

Taxon
Spinacia oleraceaSpinacia oleraceat0
Treatment
10 and 117 mg L − 1 concentration of Zn and Ke0
Outcome
Hydrogen peroxide (H 2 O 2 )e0
Direction
decreasede0
Value
29%e0

Not reportedComparator

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Spinacia oleracea
Spinacia oleracea · TaxonRasbak · CC BY-SA 3.0 · Wikimedia Commons ↗

Verbatim

e0

“Hydrogen peroxide (H 2 O 2 ) was decreased also by 29% and 14% at 10 and 117 mg L − 1 concentration of Zn and K”

✓ located verbatim in the source · abstract, characters 1249–1360 · show in text ↑
t0

“Spinacia oleracea”

✓ located verbatim in the source · title, characters 135–152 · show in text ↑
Intervention effectobservedoriginal resultpositivemeasured

Claim · model-written summary

K at 117 mg L − 1 decreased hydrogen peroxide 14%.

Taxon
Spinacia oleraceaSpinacia oleraceat0
Treatment
10 and 117 mg L − 1 concentration of Zn and Ke0
Outcome
Hydrogen peroxide (H 2 O 2 )e0
Direction
decreasede0
Value
14%e0

Not reportedComparator

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Spinacia oleracea
Spinacia oleracea · TaxonRasbak · CC BY-SA 3.0 · Wikimedia Commons ↗

Verbatim

e0

“Hydrogen peroxide (H 2 O 2 ) was decreased also by 29% and 14% at 10 and 117 mg L − 1 concentration of Zn and K”

✓ located verbatim in the source · abstract, characters 1249–1360 · show in text ↑
t0

“Spinacia oleracea”

✓ located verbatim in the source · title, characters 135–152 · show in text ↑
Intervention effectobservedoriginal resultpositivemeasured

Claim · model-written summary

Higher Zn increased protein content 1.4 fold.

Taxon
Spinacia oleraceaSpinacia oleraceat0
Treatment
Zne0
Outcome
protein contente0
Direction
increasede0
Value
1.4e0
Comparator
control plantse0

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Spinacia oleracea
Spinacia oleracea · TaxonRasbak · CC BY-SA 3.0 · Wikimedia Commons ↗

Verbatim

e0

“higher levels of Zn and K in the nutrient solution, increased protein content by 1.4 and 1.2 folded compared to the control plants”

✓ located verbatim in the source · abstract, characters 1367–1497 · show in text ↑
t0

“Spinacia oleracea”

✓ located verbatim in the source · title, characters 135–152 · show in text ↑
Intervention effectobservedoriginal resultpositivemeasured

Claim · model-written summary

Higher K increased protein content 1.2 fold.

Taxon
Spinacia oleraceaSpinacia oleraceat0
Treatment
Ke0
Outcome
protein contente0
Direction
increasede0
Value
1.2 foldede0
Comparator
control plantse0

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Spinacia oleracea
Spinacia oleracea · TaxonRasbak · CC BY-SA 3.0 · Wikimedia Commons ↗

Verbatim

e0

“higher levels of Zn and K in the nutrient solution, increased protein content by 1.4 and 1.2 folded compared to the control plants”

✓ located verbatim in the source · abstract, characters 1367–1497 · show in text ↑
t0

“Spinacia oleracea”

✓ located verbatim in the source · title, characters 135–152 · show in text ↑
Observationobservedoriginal resultpositivemeasured

Claim · model-written summary

SOD activity was maximal with 10 mg L − 1 Zn.

Treatment
10 mg L − 1 of Zne0
Outcome
maximum activity of superoxide dismutase (SOD)e0
Direction
maximume0

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Spinacia oleracea
Spinacia oleracea · TaxonRasbak · CC BY-SA 3.0 · Wikimedia Commons ↗

Verbatim

e0

“The maximum activity of superoxide dismutase (SOD) was recorded in spinach treated with 10 mg L − 1 of Zn”

✓ located verbatim in the source · abstract, characters 1499–1604 · show in text ↑
Intervention effectobservedoriginal resultpositivemeasured

Claim · model-written summary

APX activity increased 2.1 fold at 10 versus 0.22 mg L − 1 Zn.

Taxon
Spinacia oleraceaSpinacia oleraceat0
Treatment
10 mg L − 1 Zne0
Outcome
activity of ascorbate peroxidase (APX)e0
Direction
incremente0
Value
2.1 foldede0
Comparator
0.22 mg L − 1 concentratione0

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Spinacia oleracea
Spinacia oleracea · TaxonRasbak · CC BY-SA 3.0 · Wikimedia Commons ↗

Verbatim

e0

“The activity of ascorbate peroxidase (APX) was also affected by Zn as it showed up to 2.1 folded increment at 10 mg L − 1 Zn compared to the 0.22 mg L − 1 concentration.”

✓ located verbatim in the source · abstract, characters 1657–1826 · show in text ↑
t0

“Spinacia oleracea”

✓ located verbatim in the source · title, characters 135–152 · show in text ↑
Recommendationauthor interpretationoriginal resultpositivebasis n/a

Claim · model-written summary

Authors recommend 5 mg L − 1 Zn and 78 mg L − 1 K for quality and tolerance.

Taxon
plante0
Treatment
5 mg L − 1 Zn in combination with 78 mg L − 1 Ke0
Outcome
better quality and tolerancee0

Verbatim

e0

“supplementing hydroponic nutrient solutions with 5 mg L − 1 Zn in combination with 78 mg L − 1 K can lead to the better quality and tolerance of the plant”

✓ located verbatim in the source · abstract, characters 2181–2335 · show in text ↑

zinc atom · physiology: pigments · Spinacia oleracea (spinach)Positive and negative results

2 papers: 1 positive, 1 negative or no effect

1 in the opposite direction

  1. negative
See all 2 papers →

zinc atom · physiology: oxidative · Spinacia oleracea (spinach)Positive and negative results

3 papers: 2 positive, 1 negative or no effect

1 paper in the same direction as this paper · 1 in the opposite direction

  1. negative
  2. positive
See all 3 papers →

potassium · physiology: pigments · Spinacia oleracea (spinach)Positive and negative results

4 papers: 3 positive, 1 negative or no effect

2 papers in the same direction as this paper · 1 in the opposite direction

  1. negative
  2. positive
  3. positive
See all 4 papers →

potassium · quality: protein · Spinacia oleracea (spinach)Results agree

2 papers: 2 positive, 0 negative or no effect

1 paper in the same direction as this paper

  1. positive
See all 2 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.