Abstract
A split-plot experimental design was imposed in the year of planting and maintained for the first five growing seasons in a high density apple orchard on M.9 rootstock planted at 1.5 m (within row) × 4 m (between row) in a loamy sand soil susceptible to K deficiency when drip-irrigated. Four N-K fertigation treatments involving low (N1) and high (N2) rates of N combined with 0 (K0) or 15 g K/tree per year (K1) were applied in five replicated and randomized main plot units. Subplots consisted of three-tree plots of each of the apple cultivars Gala, Fuji, Fiesta and Spartan. Soil solution monitoring indicated the maintenance of distinctly different soil solution N and K concentrations in the respective N-K treatments during the study. The most important plant response was prevention of the development of K deficiency by the K1-fertigation treatment. Fertigation of 15 g K/tree generally increased leaf K, fruit K and Mg concentrations, fruit size and yield and fruit titratable acidity and red coloration at harvest for all cultivars. K fertigation also decreased leaf Mg and B concentrations, fruit N, P and Ca concentration and fruit firmness. In addition to leaf K concentrations <1%, K deficiency was associated with fruit K concentrations <100 mg/100 g fresh weight and soil solution K concentration <5 mg·L -1 . Increasing the rate of fertigated N when growth was constrained by K deficiency increased leaf N and Mn and decreased leaf P and B, but had no effect on tree vigor or fruit production and quality.
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Claims 14
Claim · model-written summary
Nitrogen and potassium fertigation maintained distinct soil solution N and K concentrations.
- Taxon
- Apple
Malus domesticat0 - Treatment
- N-K treatmentse0
- Outcome
- soil solution N and K concentrationse0
- Direction
- distinctly differente0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“Soil solution monitoring indicated the maintenance of distinctly different soil solution N and K concentrations in the respective N-K treatments during the study.”
t0“Apple”
Claim · model-written summary
K1 fertigation prevented potassium deficiency in apple.
- Taxon
- Apple
Malus domesticat0 - Treatment
- K1-fertigation treatmente0
- Outcome
- development of K deficiencye0
- Direction
- preventione0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“The most important plant response was prevention of the development of K deficiency by the K1-fertigation treatment.”
t0“Apple”
Claim · model-written summary
Potassium fertigation generally increased apple leaf K, fruit K, and fruit Mg concentrations.
- Taxon
- Apple
Malus domesticat0 - Treatment
- Fertigation of 15 g K/treee0
- Outcome
- leaf K, fruit K and Mg concentrationse0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“Fertigation of 15 g K/tree generally increased leaf K, fruit K and Mg concentrations, fruit size and yield and fruit titratable acidity and red coloration at harvest for all cultivars.”
t0“Apple”
Claim · model-written summary
Potassium fertigation generally increased apple fruit size and yield.
- Taxon
- Apple
Malus domesticat0 - Treatment
- Fertigation of 15 g K/treee0
- Outcome
- fruit size and yielde0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“Fertigation of 15 g K/tree generally increased leaf K, fruit K and Mg concentrations, fruit size and yield and fruit titratable acidity and red coloration at harvest for all cultivars.”
t0“Apple”
Claim · model-written summary
Potassium fertigation generally increased apple fruit titratable acidity and red coloration at harvest.
- Taxon
- Apple
Malus domesticat0 - Treatment
- Fertigation of 15 g K/treee0
- Outcome
- fruit titratable acidity and red coloration at harveste0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“Fertigation of 15 g K/tree generally increased leaf K, fruit K and Mg concentrations, fruit size and yield and fruit titratable acidity and red coloration at harvest for all cultivars.”
t0“Apple”
Claim · model-written summary
Potassium fertigation decreased apple leaf Mg and B concentrations.
- Taxon
- Apple
Malus domesticat0 - Treatment
- K fertigatione0
- Outcome
- leaf Mg and B concentrationse0
- Direction
- decreasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“K fertigation also decreased leaf Mg and B concentrations, fruit N, P and Ca concentration and fruit firmness.”
t0“Apple”
Claim · model-written summary
Potassium fertigation decreased apple fruit N, P, and Ca concentration.
- Taxon
- Apple
Malus domesticat0 - Treatment
- K fertigatione0
- Outcome
- fruit N, P and Ca concentratione0
- Direction
- decreasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“K fertigation also decreased leaf Mg and B concentrations, fruit N, P and Ca concentration and fruit firmness.”
t0“Apple”
Claim · model-written summary
Potassium fertigation decreased apple fruit firmness.
- Taxon
- Apple
Malus domesticat0 - Treatment
- K fertigatione0
- Outcome
- fruit firmnesse0
- Direction
- decreasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“K fertigation also decreased leaf Mg and B concentrations, fruit N, P and Ca concentration and fruit firmness.”
t0“Apple”
Claim · model-written summary
Apple K deficiency was associated with fruit K concentrations below 100 mg/100 g fresh weight.
- Taxon
- Apple
Malus domesticat0 - Organ / stage
- fruite0
- Outcome
- K deficiencye0
- Value
- <100 mg/100 g fresh weighte0
- Qualifier
- fruit K concentrations <100 mg/100 g fresh weighte0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“In addition to leaf K concentrations <1%, K deficiency was associated with fruit K concentrations <100 mg/100 g fresh weight and soil solution K concentration <5 mg·L -1 .”
t0“Apple”
Claim · model-written summary
Apple K deficiency was associated with soil solution K concentration below 5 mg·L -1.
- Taxon
- Apple
Malus domesticat0 - Outcome
- K deficiencye0
- Value
- <5 mg·L -1e0
- Qualifier
- soil solution K concentration <5 mg·L -1e0
- Setting
- soil solutione0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“In addition to leaf K concentrations <1%, K deficiency was associated with fruit K concentrations <100 mg/100 g fresh weight and soil solution K concentration <5 mg·L -1 .”
t0“Apple”
Claim · model-written summary
Apple K deficiency was indicated by leaf K concentration below 1%.
- Taxon
- Apple
Malus domesticat0 - Organ / stage
- leafe0
- Outcome
- K deficiencye0
- Value
- <1%e0
- Qualifier
- leaf K concentrations <1%e0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“In addition to leaf K concentrations <1%, K deficiency was associated with fruit K concentrations <100 mg/100 g fresh weight and soil solution K concentration <5 mg·L -1 .”
t0“Apple”
Claim · model-written summary
Increasing fertigated N under K deficiency increased apple leaf N and Mn.
- Taxon
- Apple
Malus domesticat0 - Treatment
- Increasing the rate of fertigated Ne0
- Outcome
- leaf N and Mne0
- Direction
- increasede0
- Qualifier
- when growth was constrained by K deficiencye0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“Increasing the rate of fertigated N when growth was constrained by K deficiency increased leaf N and Mn and decreased leaf P and B, but had no effect on tree vigor or fruit production and quality.”
t0“Apple”
Claim · model-written summary
Increasing fertigated N under K deficiency decreased apple leaf P and B.
- Taxon
- Apple
Malus domesticat0 - Treatment
- Increasing the rate of fertigated Ne0
- Outcome
- leaf P and Be0
- Direction
- decreasede0
- Qualifier
- when growth was constrained by K deficiencye0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“Increasing the rate of fertigated N when growth was constrained by K deficiency increased leaf N and Mn and decreased leaf P and B, but had no effect on tree vigor or fruit production and quality.”
t0“Apple”
Claim · model-written summary
Increasing fertigated N under K deficiency had no effect on apple tree vigor, fruit production, or quality.
- Taxon
- Apple
Malus domesticat0 - Treatment
- Increasing the rate of fertigated Ne0
- Outcome
- tree vigor or fruit production and qualitye0
- Direction
- no effecte0
- Qualifier
- when growth was constrained by K deficiencye0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“Increasing the rate of fertigated N when growth was constrained by K deficiency increased leaf N and Mn and decreased leaf P and B, but had no effect on tree vigor or fruit production and quality.”
t0“Apple”
The same questions in other papers
fertilization · nutrient: content · Malus domestica (apple)Positive and negative results
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See all 178 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.