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 concentrations averaged 0.82% dry mass by the third growing season, indicating deficiency.
- Taxon
- Malus × domestica Borkh.
Malus domesticae0 - Outcome
- Leaf K concentrationse1
- Value
- 0.82% dry masse1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“apple ( Malus × domestica Borkh.) trees on M.9 rootstock”
e1“Leaf K concentrations averaged 0.82% dry mass, indicating deficiency, by the third growing season”
Claim · model-written summary
Extractable soil K concentrations of 50-60 μg·g -1 soil coincided with leaf K deficiency in a narrow soil volume near the emitters.
- Taxon
- Malus × domestica Borkh.Malus domesticae0
- Outcome
- extractable soil K concentrationse2
- Value
- 50-60 μg·g -1 soile2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“apple ( Malus × domestica Borkh.) trees on M.9 rootstock”
e2“extractable soil K concentrations of 50-60 μg·g -1 soil”
Claim · model-written summary
Additions of K reversed the decline in leaf K concentration.
- Taxon
- Malus × domestica Borkh.Malus domesticae0
- Treatment
- additions of K at 15-30 g/treee3
- Outcome
- leaf K concentratione3
- Direction
- reversede3
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“apple ( Malus × domestica Borkh.) trees on M.9 rootstock”
e3“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”
Claim · model-written summary
Additions of K increased fruit K concentration.
- Taxon
- Malus × domestica Borkh.Malus domesticae0
- Treatment
- additions of K at 15-30 g/treee3
- Outcome
- fruit K concentratione3
- Direction
- increasede3
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“apple ( Malus × domestica Borkh.) trees on M.9 rootstock”
e3“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”
Claim · model-written summary
K-fertilization increased fruit red color, size and titratable acidity only when leaf K concentration was below 1%.
- Taxon
- Malus × domestica Borkh.Malus domesticae0
- Treatment
- K-fertilizatione4
- Outcome
- fruit red color, size, and titratable aciditye4
- Direction
- increasede4
- Qualifier
- only when leaf K concentration was <1%e4
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“apple ( Malus × domestica Borkh.) trees on M.9 rootstock”
e4“K-fertilization increased fruit red color, size, and titratable acidity only when leaf K concentration was <1%”
Claim · model-written summary
K application did not change fruit Ca concentration or incidence of bitter pit or coreflush.
- Taxon
- Malus × domestica Borkh.Malus domesticae0
- Treatment
- K applicatione5
- Outcome
- Fruit Ca concentration and incidence of bitter pit or coreflushe5
- Direction
- unaffectede5
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“apple ( Malus × domestica Borkh.) trees on M.9 rootstock”
e5“Fruit Ca concentration and incidence of bitter pit or coreflush were unaffected by K application”
Claim · model-written summary
NPK-fertigation commencing at tree establishment is recommended for high-density apple orchards on coarse-textured soils.
- Taxon
- appleMalus domesticae6
- Outcome
- NPK-fertigation commencing upon tree establishmente6
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“apple ( Malus × domestica Borkh.) trees on M.9 rootstock”
e6“NPK-fertigation commencing upon tree establishment is recommended for high-density apple orchards planted on similar coarse-textured soils”
The same questions in other papers
potassium · disease · Malus domestica (apple)Positive and negative results
2 papers in the same direction as this paper · 6 in the opposite direction
- positive
- positive
- positive
5 papers more in this group
See all 9 papers →potassium · quality: sugar starch · Malus domestica (apple)Positive and negative results
9 papers in the same direction as this paper · 3 in the opposite direction
- no effect
- no effect
- no effect
9 papers more in this group
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.