Effect of Foliar Application with Potassium Rates and Zinc Sources on Washington Navel Orange Trees

Abstract

This investigation was carried out during two successive seasons (2020 and 2021) to study the effect of foliar application of potassium sulfate rates combined and different sources of zinc on Washington Navel orange (Citrus sinensis) trees grafted on sour orange rootstock (Citrus aurantium). Seven foliar spray treatments are conducted as follows: three different concentrations of potassium sulfate at 1, 2, and 3% combined with two sources of zinc: sugar alcohol zinc (SA-Zn) at 0.5% and chelated zinc (Zn-EDTA) at 0.5%, in addition to the control treatment. The best results were obtained by spraying potassium sulfate at 2% and sugar alcohol zinc (SA-Zn) at 0.5%, which was superior to improving tree nutritional status, fruit set percentage, yield efficiency , bio-chemical contents, mineral content of leaves and fruit quality.

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Claims 2

Intervention effectobservedoriginal resultpositivemeasured

Claim · model-written summary

Spraying 2% potassium sulfate with 0.5% sugar alcohol zinc was superior to the control for tree nutritional status, fruit set percentage and yield efficiency.

Taxon: Washington Navel orangeCitrus sinensise2
Material: sour orange rootstocke2
Treatment: spraying potassium sulfate at 2% and sugar alcohol zinc (SA-Zn) at 0.5%e0
Outcome: tree nutritional status, fruit set percentage, yield efficiencye1
Direction: superiore1
Comparator: control treatmente4
Setting: two successive seasons (2020 and 2021)e3

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

*Citrus sinensis* · TaxonEllen Levy Finch ( Elf ) · CC BY-SA 3.0 · Wikimedia Commons ↗

Verbatim

e0
“The best results were obtained by spraying potassium sulfate at 2% and sugar alcohol zinc (SA-Zn) at 0.5%”
✓ located verbatim in the source · abstract, characters 562–667 · show in text ↑

e1
“which was superior to improving tree nutritional status, fruit set percentage, yield efficiency”
✓ located verbatim in the source · abstract, characters 669–764 · show in text ↑

e2
“Washington Navel orange (Citrus sinensis) trees grafted on sour orange rootstock (Citrus aurantium)”
✓ located verbatim in the source · abstract, characters 192–291 · show in text ↑

e3
“This investigation was carried out during two successive seasons (2020 and 2021)”
✓ located verbatim in the source · abstract, characters 0–80 · show in text ↑

e4
“in addition to the control treatment”
✓ located verbatim in the source · abstract, characters 524–560 · show in text ↑

Intervention effectobservedoriginal resultpositivemeasured

Claim · model-written summary

Spraying 2% potassium sulfate with 0.5% sugar alcohol zinc was superior to the control for bio-chemical contents, leaf mineral content and fruit quality.

Taxon: Washington Navel orangeCitrus sinensise2
Treatment: spraying potassium sulfate at 2% and sugar alcohol zinc (SA-Zn) at 0.5%e0
Outcome: bio-chemical contents, mineral content of leaves and fruit qualitye5
Direction: superiore5
Comparator: control treatmente4

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

Verbatim

e0
“The best results were obtained by spraying potassium sulfate at 2% and sugar alcohol zinc (SA-Zn) at 0.5%”
✓ located verbatim in the source · abstract, characters 562–667 · show in text ↑

e2
“Washington Navel orange (Citrus sinensis) trees grafted on sour orange rootstock (Citrus aurantium)”
✓ located verbatim in the source · abstract, characters 192–291 · show in text ↑

e4
“in addition to the control treatment”
✓ located verbatim in the source · abstract, characters 524–560 · show in text ↑

e5
“which was superior to improving tree nutritional status, fruit set percentage, yield efficiency, bio-chemical contents, mineral content of leaves and fruit quality”
✓ located verbatim in the source · abstract, characters 669–832 · show in text ↑

zinc atom · yield · Citrus sinensis (sweet orange)Results differ

19 papers: 17 positive, 2 negative or no effect

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

no effect
Zn, B and Mg did not significantly affect yield.
Foliar Applications of Essential Nutrients on Growth and Yield of ‘Valencia’ Sweet Orange Infected with Huanglongbing · 2016
Opposite direction
no effect
Zn sprays did not improve yield, fruit number or average fruit weight of orange and grapefruit trees.
Productivity, growth, and leaf mineral composition of orange and grapefruit trees foliar‐sprayed with zinc and manganese · 1991
Opposite direction
positive
The maximum fruit yield of sweet orange was obtained with 0.4 kg Zn ha(-1) and 0.2 kg Mn ha(-1) sprayed with urea and surfactant.
Effect of Foliar Application of Micronutrients on the Yield and Quality of Sweet Orange (Citrus sinensis L.) · 2007
Same direction

15 papers more in this group

See all 19 papers →

salicylic acid · quality: grain · Citrus sinensis (sweet orange)Positive and negative results

2 papers: 1 positive, 1 negative or no effect

1 in the opposite direction

no effect
Cinnamon extract combined with SA did not affect fruit quality.
Transcriptional and biochemical profiling of defense enzymes in Citrus sinensis during salicylic acid and cinnamon mediated suppression of green and blue mold · 2022 · compared with control
Opposite direction

See all 2 papers →

zinc atom · quality: grain · Citrus sinensis (sweet orange)Results agree

4 papers: 4 positive, 0 negative or no effect

3 papers in the same direction as this paper

positive
The best yield and fruit quality were significantly obtained with 0.4% yeast + 1.0% zinc, followed by 0.4% yeast + 0.5% zinc and 0.2% yeast + 1.0% zinc.
The beneficial effects of yeast and zinc sulphate on yield and fruit quality of Navel orange trees. · 2010
Same direction
positive
Zn+Cu sprays reduced granulation and improved fruit quality more than other micronutrients.
Effect of Soil and Foliar Applications of Zn and Foliar Applications of Cu, Mn, Fe Alone and in Combination with Zn on the Incidence of Chlorosis, Fruit Fall, Granulation and Fruit Quality in Sweet Orange [Citrus Sinensis (L.) Osbeck] Variety Blood Red · 1972 · compared with other micro-nutrient treatments
Same direction
positive
Three applications of the nutrient and citric acid mixture promoted yield and fruit quality in Washington Navel orange trees.
EFFECT OF SPRAYING SOME NUTRIENTS AND CITRIC ACID ON FRUITING OF WASHINGTON NAVEL ORANGE TREES · 2015
Same direction

See all 4 papers →

salicylic acid · yield · Citrus sinensis (sweet orange)Results agree

5 papers: 5 positive, 0 negative or no effect

4 papers in the same direction as this paper

1 paper more in this group

See all 5 papers →

potassium sulfate · yield · Citrus sinensis (sweet orange)Results agree

7 papers: 7 positive, 0 negative or no effect

6 papers in the same direction as this paper

positive
Potassium sulphate at 1.5 and 3.0% improved fruit yield versus water spray.
Effect of foliar application of potassium and its spray schedule on yield and yield parameters of sweet orange (Citrus sinensis Osbeck) cv. Jaffa · 2017 · compared with water spray
Same direction
positive
Soil K 2 SO 4 with Aldicarb significantly increased fruit size of Valencia orange trees.
The Influence of Potassium Applications and Nematocides on the Potassium Nutrition of ‘Valencia’ Orange Trees on Replant Citrus Soil1 · 1977
Same direction
positive
Fruit yield of sweet orange increased with increasing K doses of KNO3 and K2SO4.
Nutritional Status of Leaf and Fruit Yield of Sweet Orange Influenced by Foliar Application of Potassium · 2016
Same direction

3 papers more in this group

See all 7 papers →

application · quality: grain · Citrus sinensis (sweet orange)Positive and negative results

16 papers: 10 positive, 6 negative or no effect

9 papers in the same direction as this paper · 6 in the opposite direction

no effect
Growth regulator sprays generally did not adversely affect internal fruit quality.
Growth Regulators, Fruit Drop, Yield, and Quality of Navel Orange in Florida · 1984
Opposite direction
no effect
Sulphuric acid spray did not affect fruit quality parameters.
FOLIAR TREATMENTS AS A STRATEGY TO CONTROL IRON CHLOROSIS IN ORANGE TREES · 2002
Opposite direction
no effect
Fruit quality showed no significant difference across the foliar boron treatments.
Effect of foliar boron sprays on yield and fruit quality of navel oranges · 1999
Opposite direction

12 papers more in this group

See all 16 papers →

application · yield · Citrus sinensis (sweet orange)Positive and negative results

77 papers: 65 positive, 12 negative or no effect

64 papers in the same direction as this paper · 12 in the opposite direction

no effect
The same materials at 13 weeks after midbloom did not reduce summer drop.
Growth Regulators, Fruit Drop, Yield, and Quality of Navel Orange in Florida · 1984
Opposite direction
no effect
Zn sprays did not improve yield, fruit number or average fruit weight of orange and grapefruit trees.
Productivity, growth, and leaf mineral composition of orange and grapefruit trees foliar‐sprayed with zinc and manganese · 1991
Opposite direction
negative
Calcium sprays as CaCl2 applied early in the season at 0.33% caused unacceptable fruit drop.
Calcium-spray treatments for ameliorating albedo breakdown in navel oranges · 2002
Opposite direction

73 papers more in this group

See all 77 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.