Abstract
Introduction. The objective of the present paper was to evaluate the effects of N, P and K, and their interactions, on fruit yield and quality of two sweet orange varieties, Valencia and Pêra, grown on tropical soils in the State of São Paulo, Brazil, over four seasons. Materials and methods. Two experiments were set up in a fractional factorial design of the ½ (4 × 4 × 4) type, with four rates of N [(30, 100, 170 and 240) kg·ha–1·year–1], P [(9, 27, 45 and 63) kg·ha–1·year–1)] and K [(24, 91, 158 and 225) kg·ha–1·year–1] applied to the soil surface during the rainy season. Functions of the type y = b0 + b11N + b11N2 + b2P + b22P2 + b3K + b33K2 + b12NP + b13NK + b23PK were fitted for dependent variables: fruit yield and mass, juice content, and total soluble solids and acidity concentrations. Results. Maximum yield of Pêra and Valencia was attained, respectively, with N rates of (189 and 193) kg·ha–1. Fruit yield response to P and K fertilization for both cultivars was dependent on soil nutrient availability. Fruit size of Valencia trees was markedly affected by rates of K over 225 kg·ha–1. Yield of soluble solids per box of fruits (40.8 kg) decreased as leaf K concentration varied from (10 to 12) g·kg–1. Conclusion. Soil testing and leaf analysis play an important role in defining fruit yield and quality for citrus trees. The best nutritional program may vary depending on the destination of fruit to either juice production or the fresh market.
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Claims 8
Claim · model-written summary
Pêra yield reached a maximum at 189 kg·ha–1 nitrogen.
- Taxon
- sweet oranges
Citrus sinensist0 - Material
- Pêrae0
- Treatment
- N ratese0
- Outcome
- yielde0
- Direction
- Maximume0
- Value
- 189e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Maximum yield of Pêra and Valencia was attained, respectively, with N rates of (189 and 193) kg·ha–1.”
t0“sweet oranges”
Claim · model-written summary
Valencia yield reached a maximum at 193 kg·ha–1 nitrogen.
- Taxon
- sweet orangesCitrus sinensist0
- Material
- Valenciae0
- Treatment
- N ratese0
- Outcome
- yielde0
- Direction
- Maximume0
- Value
- 193e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Maximum yield of Pêra and Valencia was attained, respectively, with N rates of (189 and 193) kg·ha–1.”
t0“sweet oranges”
Claim · model-written summary
Yield responses of both cultivars to phosphorus fertilization depended on soil nutrient availability.
- Taxon
- sweet orangesCitrus sinensist0
- Treatment
- P and K fertilizatione0
- Outcome
- Fruit yield responsee0
- Qualifier
- soil nutrient availabilitye0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Fruit yield response to P and K fertilization for both cultivars was dependent on soil nutrient availability.”
t0“sweet oranges”
Claim · model-written summary
Yield responses of both cultivars to potassium fertilization depended on soil nutrient availability.
- Taxon
- sweet orangesCitrus sinensist0
- Treatment
- P and K fertilizatione0
- Outcome
- Fruit yield responsee0
- Qualifier
- soil nutrient availabilitye0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Fruit yield response to P and K fertilization for both cultivars was dependent on soil nutrient availability.”
t0“sweet oranges”
Claim · model-written summary
Potassium rates above 225 kg·ha–1 markedly affected Valencia fruit size, with direction unstated.
- Taxon
- sweet orangesCitrus sinensist0
- Material
- Valenciae0
- Treatment
- rates of K over 225 kg·ha–1e0
- Outcome
- Fruit sizee0
Not reportedComparatorDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Fruit size of Valencia trees was markedly affected by rates of K over 225 kg·ha–1.”
t0“sweet oranges”
Claim · model-written summary
Soluble solids yield per fruit box decreased as leaf potassium concentration varied from 10 to 12 g·kg–1.
- Taxon
- sweet orangesCitrus sinensist0
- Organ / stage
- leafe0
- Outcome
- Yield of soluble solids per box of fruitse0
- Direction
- decreasede0
- Value
- 40.8 kge0
- Qualifier
- 10 to 12e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Yield of soluble solids per box of fruits (40.8 kg) decreased as leaf K concentration varied from (10 to 12) g·kg–1.”
t0“sweet oranges”
Claim · model-written summary
Soil testing and leaf analysis are important for defining citrus yield and quality.
- Outcome
- Soil testing and leaf analysise0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Soil testing and leaf analysis play an important role in defining fruit yield and quality for citrus trees.”
Claim · model-written summary
The best citrus nutrition program may vary by destination for juice or fresh fruit.
- Taxon
- sweet orangesCitrus sinensist0
- Outcome
- best nutritional programe0
- Qualifier
- juice production or the fresh markete0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The best nutritional program may vary depending on the destination of fruit to either juice production or the fresh market.”
t0“sweet oranges”
The same questions in other papers
nitrogen · yield · Citrus sinensis (sweet orange)Results differ
38 papers in the same direction as this paper · 8 in the opposite direction · 1 reporting no difference from an alternative
- negative
- positive
- positive
44 papers more in this group
See all 48 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.