Abstract
Various schedules of 40 g N and 17.5 g P/tree per year were applied with irrigation water (fertigation) to `Summerland McIntosh' apple ( Malus × domestica Borkh.) trees on M.9 rootstock commencing the year of planting. Leaf K concentrations averaged 0.82% dry mass, indicating deficiency, by the third growing season. This coincided with extractable soil K concentrations of 50-60 μg·g -1 soil in a narrow volume of the coarse-textured soil located within 0.3 m of the emitters. The decline in leaf K concentration was reversed and fruit K concentration increased by additions of K at 15-30 g/tree applied either as granular KCl directly beneath the emitters in spring or as KCl applied as a fertigant in the irrigation water. K-fertilization increased fruit red color, size, and titratable acidity only when leaf K concentration was <1%. Fruit Ca concentration and incidence of bitter pit or coreflush were unaffected by K application. NPK-fertigation commencing upon tree establishment is recommended for high-density apple orchards planted on similar coarse-textured soils.
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Claims 7
Claim · model-written summary
Leaf K averaged 0.82% dry mass by the third growing season, indicating deficiency.
- Taxon
- Apple
Malus domesticat0 - Outcome
- Leaf K concentrationse0
- Value
- 0.82% dry masse0
- Qualifier
- by the third growing seasone0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Leaf K concentrations averaged 0.82% dry mass, indicating deficiency, by the third growing season.”
t0“Apple”
Claim · model-written summary
Leaf K deficiency coincided with soil K of 50-60 μg·g -1 soil within 0.3 m of emitters.
- Taxon
- AppleMalus domesticat0
- Compound
- Ke0
- Outcome
- Leaf K concentrationse1
- Value
- 50-60 μg·g -1 soile0
- Setting
- within 0.3 m of the emitterse0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“This coincided with extractable soil K concentrations of 50-60 μg·g -1 soil in a narrow volume of the coarse-textured soil located within 0.3 m of the emitters.”
e1“Leaf K concentrations averaged 0.82% dry mass, indicating deficiency, by the third growing season.”
t0“Apple”
Claim · model-written summary
K additions of 15-30 g/tree reversed declining leaf K concentrations.
- Taxon
- AppleMalus domesticat0
- Treatment
- additions of K at 15-30 g/treee0
- Outcome
- decline in leaf K concentratione0
- Direction
- reversede0
- Qualifier
- applied either as granular KCl directly beneath the emitters in spring or as KCl applied as a fertigant in the irrigation watere0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The decline in leaf K concentration was reversed and fruit K concentration increased by additions of K at 15-30 g/tree applied either as granular KCl directly beneath the emitters in spring or as KCl applied as a fertigant in the irrigation water.”
t0“Apple”
Claim · model-written summary
K additions of 15-30 g/tree increased fruit K concentrations.
- Taxon
- AppleMalus domesticat0
- Treatment
- additions of K at 15-30 g/treee0
- Outcome
- fruit K concentratione0
- Direction
- increasede0
- Qualifier
- applied either as granular KCl directly beneath the emitters in spring or as KCl applied as a fertigant in the irrigation watere0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“fruit K concentration increased by additions of K at 15-30 g/tree applied either as granular KCl directly beneath the emitters in spring or as KCl applied as a fertigant in the irrigation water.”
t0“Apple”
Claim · model-written summary
K fertilization increased fruit red color, size and titratable acidity only when leaf K was below 1%.
- Taxon
- AppleMalus domesticat0
- Treatment
- K-fertilizatione0
- Outcome
- fruit red color, size, and titratable aciditye0
- Direction
- increasede0
- Qualifier
- only when leaf K concentration was <1%e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“K-fertilization increased fruit red color, size, and titratable acidity only when leaf K concentration was <1%.”
t0“Apple”
Claim · model-written summary
K application did not affect fruit Ca concentration or bitter pit and coreflush incidence.
- Taxon
- AppleMalus domesticat0
- Treatment
- K applicatione0
- Outcome
- Fruit Ca concentration and incidence of bitter pit or coreflushe0
- Direction
- unaffectede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Fruit Ca concentration and incidence of bitter pit or coreflush were unaffected by K application.”
t0“Apple”
Claim · model-written summary
NPK fertigation from establishment is recommended for high-density apple orchards on similar coarse-textured soils.
- Taxon
- appleMalus domesticae0
- Outcome
- NPK-fertigation commencing upon tree establishmente0
- Qualifier
- high-density apple orchards planted on similar coarse-textured soilse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“NPK-fertigation commencing upon tree establishment is recommended for high-density apple orchards planted on similar coarse-textured soils.”
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See all 13 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.