Abstract
A randomized, complete block, split-plot experimental design with six replicates was established and maintained annually for the first five fruiting seasons (1999 to 2003) in a high-density apple [ Malus sylvestris (L) Mill var. domestica (Borkh.) Mansf] orchard on M.9 rootstock planted in Apr. 1998. Main plot treatments involved eight different nutrient regimes, each containing three tree subplots of each of five different cultivars (Ambrosia, Cameo, Fuji, Gala, and Silken). This report compares a +phosphorus (P) treatment, involving annual fertigation at bloom time of 20 g P/tree as ammonium polyphosphate (10N–15P–0K), to a −P treatment. Both treatments also received nitrogen, potassium, and boron nutrients through fertigation. Drip fertigation of P increased 2 M KCl-extractable P to 0.4-m depth within 0.5-m distance of the drippers. Leaf and fruit P concentrations were consistently increased by the +P treatment with few differences among cultivars. P-fertigated trees also had a 20% increase in cumulative yield overall cultivars during the first five fruiting seasons. Standard fruit quality measurements, including fruit size, soluble solids concentration, titratable acidity, and red coloration were unaffected by P application. However, reductions in incidence of water core at harvest, increased resistance to browning, and elevated antioxidant content of harvested fruit measured in some years imply a role for P in apple membrane stability. The cumulative results indicate that applications of 20 g P as ammonium polyphosphate annually at bloom would be advantageous for apples receiving adequate fertigated applications of nitrogen, potassium, and boron. Best apple performance was associated with leaf P concentrations above 2.2 mg·g −1 dry weight and fruit P concentrations between 100 and 120 mg·kg −1 dry weight.
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Claims 10
Claim · model-written summary
Phosphorus fertigation increased extractable soil phosphorus near drippers.
- Taxon
- apple
Malus domesticat0 - Treatment
- Drip fertigation of Pe0
- Outcome
- 2 M KCl-extractable Pe0
- Direction
- increasede0
- Qualifier
- to 0.4-m depth within 0.5-m distance of the dripperse0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Drip fertigation of P increased 2 M KCl-extractable P to 0.4-m depth within 0.5-m distance of the drippers”
t0“Apple Tree Phosphorus Nutrition”
Claim · model-written summary
Phosphorus fertigation increased leaf and fruit phosphorus concentrations across cultivars.
- Taxon
- appleMalus domesticat0
- Treatment
- +P treatmente0
- Outcome
- Leaf and fruit P concentrationse0
- Direction
- increasede0
- Qualifier
- few differences among cultivarse0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Leaf and fruit P concentrations were consistently increased by the +P treatment with few differences among cultivars”
t0“Apple Tree Phosphorus Nutrition”
Claim · model-written summary
Phosphorus fertigation raised cumulative yield by 20% over five fruiting seasons.
- Taxon
- appleMalus domesticat0
- Treatment
- P-fertigatede0
- Outcome
- cumulative yielde0
- Direction
- increasee0
- Value
- 20%e0
- Qualifier
- during the first five fruiting seasonse0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“P-fertigated trees also had a 20% increase in cumulative yield overall cultivars during the first five fruiting seasons”
t0“Apple Tree Phosphorus Nutrition”
Claim · model-written summary
Phosphorus application did not affect fruit size, soluble solids, titratable acidity, or red coloration.
- Taxon
- appleMalus domesticat0
- Treatment
- P applicatione0
- Outcome
- fruit size, soluble solids concentration, titratable acidity, and red coloratione0
- Direction
- unaffectede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Standard fruit quality measurements, including fruit size, soluble solids concentration, titratable acidity, and red coloration were unaffected by P application”
t0“Apple Tree Phosphorus Nutrition”
Claim · model-written summary
Phosphorus treatment reduced water core incidence at harvest.
- Taxon
- appleMalus domesticat0
- Treatment
- P applicatione1
- Outcome
- incidence of water core at harveste0
- Direction
- reductionse0
- Qualifier
- measured in some yearse0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“reductions in incidence of water core at harvest, increased resistance to browning, and elevated antioxidant content of harvested fruit measured in some years”
t0“Apple Tree Phosphorus Nutrition”
e1“P application”
Claim · model-written summary
Phosphorus treatment increased resistance to browning in harvested fruit in some years.
- Taxon
- appleMalus domesticat0
- Treatment
- P applicatione1
- Outcome
- resistance to browninge0
- Direction
- increasede0
- Qualifier
- measured in some yearse0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“increased resistance to browning, and elevated antioxidant content of harvested fruit measured in some years”
t0“Apple Tree Phosphorus Nutrition”
e1“P application”
Claim · model-written summary
Phosphorus treatment elevated antioxidant content of harvested fruit in some years.
- Taxon
- appleMalus domesticat0
- Treatment
- P applicatione1
- Outcome
- antioxidant content of harvested fruite0
- Direction
- elevatede0
- Qualifier
- measured in some yearse0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“elevated antioxidant content of harvested fruit measured in some years”
t0“Apple Tree Phosphorus Nutrition”
e1“P application”
Claim · model-written summary
The authors recommend annual bloom applications of 20 g phosphorus as ammonium polyphosphate for adequately fertigated apples.
- Taxon
- applesMalus domesticae0
- Outcome
- applications of 20 g P as ammonium polyphosphate annually at bloome0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“applications of 20 g P as ammonium polyphosphate annually at bloom would be advantageous for apples receiving adequate fertigated applications of nitrogen, potassium, and boron”
Claim · model-written summary
Best apple performance was associated with leaf phosphorus above 2.2 mg per gram dry weight.
- Taxon
- appleMalus domesticae0
- Organ / stage
- leafe0
- Outcome
- Best apple performancee0
- Value
- above 2.2 mg·g −1 dry weighte0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Best apple performance was associated with leaf P concentrations above 2.2 mg·g −1 dry weight and fruit P concentrations between 100 and 120 mg·kg −1 dry weight”
Claim · model-written summary
Best apple performance was associated with fruit phosphorus between 100 and 120 mg per kilogram dry weight.
- Taxon
- appleMalus domesticat0
- Organ / stage
- fruite0
- Outcome
- Best apple performancee0
- Value
- between 100 and 120 mg·kg −1 dry weighte0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Best apple performance was associated with leaf P concentrations above 2.2 mg·g −1 dry weight and fruit P concentrations between 100 and 120 mg·kg −1 dry weight”
t0“Apple Tree Phosphorus Nutrition”
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See all 12 papers →phosphorus · quality: sugar starch · Malus domestica (apple)Results agree
1 paper in the same direction as this paper
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phosphorus · molecular: metabolites · Malus domestica (apple)Results agree
2 papers in the same direction as this paper
- positive
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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.