Abstract
Nitrogen requirements at bulb initiation for production of intermediate-day onions Article in Acta horticulturae · October 2016 DOI: 10.17660/ActaHortic.2016.1142.11 1st Rui Machado 16.44 · Universidade de Évora 2nd David R. Bryla 30.16 · United States Department of Agriculture Abstract Nitrogen requirements at bulb initiation for production of intermediate-day onions Authors: R.M.A. Machado, D.R. Bryla Keywords: Allium cepa, crop growth, nitrogen uptake, soil nitrate Abstract: The effect of nitrogen application on growth, nitrogen (N) uptake, yield, and quality of intermediate-day onion (Allium cepa 'Guimar') was evaluated in the field in southern Portugal. Plants were fertilized with 30 kg ha-1 N at transplanting, 10 kg ha-1 N at 29 days after transplanting (DAT) during early leaf growth, and with 0, 20, 40 and 60 kg ha-1 N at 51 DAT at the initiation of bulbing. The root system of plants in each treatment were concentrated in the top 0.1 m of soil and limited to 0.3 m depth but neither root length density nor rooting depth were affected by N application during later stages of bulb development. Leaf and bulb dry matter, on the other hand, increased linearly with N rate during bulb growth (85 DAT) and at harvest (114 DAT), respectively. Soil nitrate-N (NO3-N) at 0-0.3 m depth likewise increased linearly with N rate during bulb growth but declined from 15-30 mg kg-1 at bulbing to >10 mg kg-1 in each treatment by harvest. A substantial amount of N in the plants, which ranged from 302-525 mg, was taken up from the soil. Application of 60 kg ha-1 N resulted in luxury consumption. Yield (fresh bulb weight) increased from 0.19 kg plant-1 with no N at bulbing to as much as 0.28 kg plant-1 with 60 kg ha-1 N. Bulbs harvested from plants fertilized 40-60 kg ha-1 N averaged 8.2-8.5 cm in diameter, while those from plants with no N at bulbing averaged only 7.2 cm in diameter. Application of N fertilizer is thus recommended at bulbing to increase N uptake, yield, and bulb size of intermediate-day onions, particularly in dry Mediterranean climates where many onions are produced. Other components of quality, including neck diameter, bulb water content, total soluble solids, and juice pH, were not affect by N applied at bulbing.
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Claims 12
Claim · model-written summary
Nitrogen application did not affect root length density or rooting depth during later stages of bulb development in intermediate-day onion.
- Taxon
- Allium cepa
Allium cepae2 - Material
- Guimare2
- Organ / stage
- later stages of bulb developmente1
- Treatment
- N applicatione1
- Outcome
- root length density nor rooting depthe1
- Direction
- no_changeinferrede1
- Setting
- in the field in southern Portugale2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“neither root length density nor rooting depth were affected by N application during later stages of bulb development”
e2“intermediate-day onion (Allium cepa 'Guimar') was evaluated in the field in southern Portugal”
Claim · model-written summary
Leaf dry matter increased linearly with N rate during bulb growth (85 DAT) in intermediate-day onion.
- Taxon
- Allium cepaAllium cepae2
- Material
- Guimare2
- Organ / stage
- Leafe3
- Treatment
- N ratee3
- Outcome
- dry mattere3
- Direction
- increasede3
- Qualifier
- during bulb growth (85 DAT)e3
- Setting
- in the field in southern Portugale2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e2“intermediate-day onion (Allium cepa 'Guimar') was evaluated in the field in southern Portugal”
e3“Leaf and bulb dry matter, on the other hand, increased linearly with N rate during bulb growth (85 DAT) and at harvest (114 DAT), respectively”
Claim · model-written summary
Bulb dry matter increased linearly with N rate at harvest (114 DAT) in intermediate-day onion.
- Taxon
- Allium cepaAllium cepae2
- Material
- Guimare2
- Organ / stage
- bulbe3
- Treatment
- N ratee3
- Outcome
- dry mattere3
- Direction
- increasede3
- Qualifier
- at harvest (114 DAT)e3
- Setting
- in the field in southern Portugale2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e2“intermediate-day onion (Allium cepa 'Guimar') was evaluated in the field in southern Portugal”
e3“Leaf and bulb dry matter, on the other hand, increased linearly with N rate during bulb growth (85 DAT) and at harvest (114 DAT), respectively”
Claim · model-written summary
Soil nitrate-N at 0-0.3 m depth increased linearly with N rate during bulb growth.
- Taxon
- Allium cepaAllium cepae2
- Material
- Guimare2
- Treatment
- N ratee4
- Outcome
- Soil nitrate-N (NO3-N)e4
- Direction
- increasede4
- Qualifier
- at 0-0.3 m depthe4
- Setting
- in the field in southern Portugale2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e2“intermediate-day onion (Allium cepa 'Guimar') was evaluated in the field in southern Portugal”
e4“Soil nitrate-N (NO3-N) at 0-0.3 m depth likewise increased linearly with N rate during bulb growth”
Claim · model-written summary
Soil nitrate-N declined from 15-30 mg kg-1 at bulbing to >10 mg kg-1 in each treatment by harvest.
- Taxon
- Allium cepaAllium cepae2
- Material
- Guimare2
- Outcome
- Soil nitrate-N (NO3-N)e4
- Direction
- declinede5
- Value
- 15-30 mg kg-1e5
- Qualifier
- to >10 mg kg-1 in each treatment by harveste5
- Setting
- in the field in southern Portugale2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e2“intermediate-day onion (Allium cepa 'Guimar') was evaluated in the field in southern Portugal”
e4“Soil nitrate-N (NO3-N) at 0-0.3 m depth likewise increased linearly with N rate during bulb growth”
e5“declined from 15-30 mg kg-1 at bulbing to >10 mg kg-1 in each treatment by harvest”
Claim · model-written summary
About 302-525 mg of N in the plants was taken up from the soil by intermediate-day onion.
- Taxon
- Allium cepaAllium cepae2
- Material
- Guimare2
- Outcome
- N in the plantse6
- Value
- 302-525 mge6
- Setting
- in the field in southern Portugale2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e2“intermediate-day onion (Allium cepa 'Guimar') was evaluated in the field in southern Portugal”
e6“A substantial amount of N in the plants, which ranged from 302-525 mg, was taken up from the soil”
Claim · model-written summary
Application of 60 kg ha-1 N resulted in luxury consumption of nitrogen by intermediate-day onion.
- Taxon
- Allium cepaAllium cepae2
- Material
- Guimare2
- Treatment
- Application of 60 kg ha-1 Ne7
- Outcome
- luxury consumptione7
- Setting
- in the field in southern Portugale2
Not reportedComparatorDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e2“intermediate-day onion (Allium cepa 'Guimar') was evaluated in the field in southern Portugal”
e7“Application of 60 kg ha-1 N resulted in luxury consumption”
Claim · model-written summary
Fresh bulb yield increased from 0.19 kg plant-1 with no N at bulbing to as much as 0.28 kg plant-1 with 60 kg ha-1 N.
- Taxon
- Allium cepaAllium cepae2
- Material
- Guimare2
- Treatment
- 60 kg ha-1 Ne3
- Outcome
- Yield (fresh bulb weight)e3
- Direction
- increasede3
- Value
- 0.28 kg plant-1e3
- Qualifier
- from 0.19 kg plant-1e3
- Comparator
- no N at bulbinge3
- Setting
- in the field in southern Portugale2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e2“intermediate-day onion (Allium cepa 'Guimar') was evaluated in the field in southern Portugal”
e3“Yield (fresh bulb weight) increased from 0.19 kg plant-1 with no N at bulbing to as much as 0.28 kg plant-1 with 60 kg ha-1 N”
Claim · model-written summary
Bulbs from plants fertilized with 40-60 kg ha-1 N were larger in diameter (8.2-8.5 cm) than bulbs from plants with no N at bulbing (7.2 cm).
- Taxon
- Allium cepaAllium cepae2
- Material
- Guimare2
- Organ / stage
- Bulbse3
- Treatment
- 40-60 kg ha-1 Ne3
- Outcome
- diametere3
- Direction
- higherinferrede3
- Value
- 8.2-8.5 cme3
- Qualifier
- 7.2 cm in diametere3
- Comparator
- no N at bulbinge3
- Setting
- in the field in southern Portugale2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e2“intermediate-day onion (Allium cepa 'Guimar') was evaluated in the field in southern Portugal”
e3“Bulbs harvested from plants fertilized 40-60 kg ha-1 N averaged 8.2-8.5 cm in diameter, while those from plants with no N at bulbing averaged only 7.2 cm in diameter”
Claim · model-written summary
N fertilizer should be applied at bulbing to increase N uptake, yield and bulb size of intermediate-day onions, particularly in dry Mediterranean climates.
Verbatim
e4“Application of N fertilizer is thus recommended at bulbing to increase N uptake, yield, and bulb size of intermediate-day onions, particularly in dry Mediterranean climates where many onions are produced”
Claim · model-written summary
Neck diameter, bulb water content and total soluble solids were not affected by N applied at bulbing.
- Taxon
- Allium cepaAllium cepae2
- Material
- Guimare2
- Treatment
- N applied at bulbinge3
- Outcome
- neck diameter, bulb water content, total soluble solidse3
- Direction
- no_changeinferrede3
- Setting
- in the field in southern Portugale2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e2“intermediate-day onion (Allium cepa 'Guimar') was evaluated in the field in southern Portugal”
e3“Other components of quality, including neck diameter, bulb water content, total soluble solids, and juice pH, were not affect by N applied at bulbing”
Claim · model-written summary
Juice pH was not affected by N applied at bulbing.
- Taxon
- Allium cepaAllium cepae2
- Material
- Guimare2
- Treatment
- N applied at bulbinge3
- Outcome
- juice pHe3
- Direction
- no_changeinferrede3
- Setting
- in the field in southern Portugale2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e2“intermediate-day onion (Allium cepa 'Guimar') was evaluated in the field in southern Portugal”
e3“Other components of quality, including neck diameter, bulb water content, total soluble solids, and juice pH, were not affect by N applied at bulbing”
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