Abstract
ABSTRACT Three field experiments were conducted in 1999 and 2000 to assess the response of shallots (Allium cepa var. ascalonicum Backer) to nitrogen fertilizer sources and rates in eastern Ethiopia. Treatments comprised three nitrogen sources, urea, ammonium nitrate and ammonium sulphate, each at 0, 50, 100, 150 and 200 kg ha−1 N. Bulb yield was significantly increased with nitrogen fertilization up to 150 kg ha−1 in the main rainy season of 2000 when supplemental irrigation was applied. However, fertilization significantly reduced growth and yield of shallot in the main rainy season of 1999 and the short rainy season of 2000 under rain-fed conditions. Fertilization tended to increase bulb number per plant while reducing mean bulb weight. The dry matter and total soluble solids of bulbs from fertilized plots were either higher than or similar to those of unfertilized shallots. Ammonium nitrate produced significantly higher yields of shallots than ammonium sulphate, but did not differ from urea. Nitrogen source did not have significant effects on plant height, leaf number, bulb weight or bulb diameter. Higher nitrogen levels increased leaf and bulb nitrogen contents at harvest. The results indicated that nitrogen fertilizer should not be used for rain-fed shallots under low moisture regimes. Supplemental irrigation is essential in order to achieve high yields with nitrogen fertilization practices.
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Claims 12
Claim · model-written summary
Bulb yield of shallot was significantly increased by nitrogen fertilization up to 150 kg ha−1 in the main rainy season of 2000 when supplemental irrigation was applied.
- Taxon
- shallots
Allium cepa var. aggregatume0 - Treatment
- nitrogen fertilization up to 150 kg ha−1e1
- Outcome
- Bulb yielde1
- Direction
- increasede1
- Qualifier
- when supplemental irrigation was appliede1
- Setting
- eastern Ethiopiae0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“shallots (Allium cepa var. ascalonicum Backer) to nitrogen fertilizer sources and rates in eastern Ethiopia”
e1“Bulb yield was significantly increased with nitrogen fertilization up to 150 kg ha−1 in the main rainy season of 2000 when supplemental irrigation was applied”
Claim · model-written summary
Nitrogen fertilization significantly reduced growth and yield of shallot in the main rainy season of 1999 and the short rainy season of 2000 under rain-fed conditions.
- Taxon
- shallotAllium cepa var. aggregatume0
- Treatment
- fertilizatione0
- Outcome
- growth and yielde0
- Direction
- reducede0
- Qualifier
- under rain-fed conditionse0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“fertilization significantly reduced growth and yield of shallot in the main rainy season of 1999 and the short rainy season of 2000 under rain-fed conditions”
Claim · model-written summary
Fertilization tended to increase bulb number per plant in shallot.
- Taxon
- shallotsAllium cepa var. aggregatume0
- Treatment
- Fertilizatione1
- Outcome
- bulb number per plante1
- Direction
- increasee1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“shallots (Allium cepa var. ascalonicum Backer)”
e1“Fertilization tended to increase bulb number per plant while reducing mean bulb weight”
Claim · model-written summary
Fertilization reduced mean bulb weight in shallot.
- Taxon
- shallotsAllium cepa var. aggregatume0
- Treatment
- Fertilizatione1
- Outcome
- mean bulb weighte1
- Direction
- reducinge1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“shallots (Allium cepa var. ascalonicum Backer)”
e1“Fertilization tended to increase bulb number per plant while reducing mean bulb weight”
Claim · model-written summary
Dry matter and total soluble solids of bulbs from fertilized plots were either higher than or similar to those of unfertilized shallots.
- Taxon
- shallotsAllium cepa var. aggregatume0
- Treatment
- fertilized plotse0
- Outcome
- dry matter and total soluble solids of bulbse0
- Direction
- higher than or similar toe0
- Comparator
- unfertilized shallotse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The dry matter and total soluble solids of bulbs from fertilized plots were either higher than or similar to those of unfertilized shallots”
Claim · model-written summary
Ammonium nitrate produced significantly higher shallot yields than ammonium sulphate.
- Taxon
- shallotsAllium cepa var. aggregatume0
- Treatment
- Ammonium nitratee0
- Outcome
- yields of shallotse0
- Direction
- highere0
- Comparator
- ammonium sulphatee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Ammonium nitrate produced significantly higher yields of shallots than ammonium sulphate, but did not differ from urea”
Claim · model-written summary
Shallot yields with ammonium nitrate did not differ from those with urea.
- Taxon
- shallotsAllium cepa var. aggregatume0
- Treatment
- Ammonium nitratee0
- Outcome
- yields of shallotse0
- Direction
- did not differe0
- Comparator
- ureae0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Ammonium nitrate produced significantly higher yields of shallots than ammonium sulphate, but did not differ from urea”
Claim · model-written summary
Nitrogen source did not have significant effects on shallot plant height or leaf number.
- Taxon
- shallotsAllium cepa var. aggregatume0
- Treatment
- Nitrogen sourcee1
- Outcome
- plant height, leaf numbere1
- Direction
- did not have significant effectse1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“shallots (Allium cepa var. ascalonicum Backer)”
e1“Nitrogen source did not have significant effects on plant height, leaf number, bulb weight or bulb diameter”
Claim · model-written summary
Nitrogen source did not have significant effects on shallot bulb weight or bulb diameter.
- Taxon
- shallotsAllium cepa var. aggregatume0
- Treatment
- Nitrogen sourcee1
- Outcome
- bulb weight or bulb diametere1
- Direction
- did not have significant effectse1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“shallots (Allium cepa var. ascalonicum Backer)”
e1“Nitrogen source did not have significant effects on plant height, leaf number, bulb weight or bulb diameter”
Claim · model-written summary
Higher nitrogen levels increased leaf and bulb nitrogen contents of shallot at harvest.
- Taxon
- shallotsAllium cepa var. aggregatume0
- Treatment
- Higher nitrogen levelse1
- Outcome
- leaf and bulb nitrogen contentse1
- Direction
- increasede1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“shallots (Allium cepa var. ascalonicum Backer)”
e1“Higher nitrogen levels increased leaf and bulb nitrogen contents at harvest”
Claim · model-written summary
Nitrogen fertilizer should not be used for rain-fed shallots under low moisture regimes.
- Taxon
- shallotsAllium cepa var. aggregatume0
- Outcome
- nitrogen fertilizer should not be usede0
- Qualifier
- under low moisture regimese0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“nitrogen fertilizer should not be used for rain-fed shallots under low moisture regimes”
Claim · model-written summary
Supplemental irrigation is essential to achieve high shallot yields with nitrogen fertilization.
- Taxon
- shallotsAllium cepa var. aggregatume0
- Treatment
- nitrogen fertilization practicese1
- Outcome
- Supplemental irrigation is essentiale1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“shallots (Allium cepa var. ascalonicum Backer)”
e1“Supplemental irrigation is essential in order to achieve high yields with nitrogen fertilization practices”
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