Abstract
Different sources of nitrogen fertilizers are being used in olive orchards, of which urea is widely used by olive growers. However, nano-chelated nitrogen (nano-N) is a newly found feature of the fertilizer with very little known information. In the current research, the impact of foliar spray of two nitrogen sources; urea (U) and nano-N on oil content and quality of olive cv. ‘Zard’ during two consecutive seasons were investigated. The olive trees were sprayed with 2.21 g (U1) and 2.95 g (U2), and 6 g nano-N1 and 8 g nano-N2 at several phenological stages of olive tree. The detailed observations showed that U1 significantly increased fruit yield. Monounsaturated fatty acid and the ratio of oleic acid to linoleic acid were increased by the nitrogen treatments, especially with nano-N2, whereas it decreased in the case of saturated fatty acid and polyunsaturated fatty acids. The application of both fertilizer sources improved the leaf mineral compositions as well as the oil quality such as free fatty acids, peroxide activity, K232 and K270 extinction coefficients, the chlorophyll and carotenoid pigments. Total phenolic content of the oil in olive trees sprayed with urea was lower than those treated with nano-N. In contrast, the oil antioxidant capacity was high in those trees treated with nano-N. Overall, the results showed that nano-fertilizer, especially nan-N2 treatment rather than urea, is an effective approach to improve oil quality.
Abstract from the paper’s OpenAlex record, shown for indexing and research. Copyright remains with the authors or the publisher. Read at the source ↗
The text the model read, with the source record’s inline markup (italics, sub- and superscripts) rendered and its character entities decoded; quote offsets refer to the raw text.
Claims 9
Claim · model-written summary
Urea dose U1 significantly increased olive fruit yield.
- Taxon
- olive
Olea europaeae1 - Material
- Zarde1
- Treatment
- 2.21 g (U1)e2
- Outcome
- fruit yielde3
- Direction
- increasede3
- Setting
- two consecutive seasonse1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“impact of foliar spray of two nitrogen sources; urea (U) and nano-N on oil content and quality of olive cv. ‘Zard’ during two consecutive seasons were investigated”
e2“The olive trees were sprayed with 2.21 g (U1) and 2.95 g (U2), and 6 g nano-N1 and 8 g nano-N2 at several phenological stages of olive tree”
e3“The detailed observations showed that U1 significantly increased fruit yield”
Claim · model-written summary
Nitrogen treatments increased the monounsaturated fatty acid content and the oleic to linoleic acid ratio of olive oil, especially with nano-N2.
- Taxon
- oliveOlea europaeae1
- Treatment
- nitrogen treatmentse4
- Outcome
- Monounsaturated fatty acid and the ratio of oleic acid to linoleic acide4
- Direction
- increasede4
- Qualifier
- especially with nano-N2e4
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“impact of foliar spray of two nitrogen sources; urea (U) and nano-N on oil content and quality of olive cv. ‘Zard’ during two consecutive seasons were investigated”
e4“Monounsaturated fatty acid and the ratio of oleic acid to linoleic acid were increased by the nitrogen treatments, especially with nano-N2, whereas it decreased in the case of saturated fatty acid and polyunsaturated fatty acids”
Claim · model-written summary
Nitrogen treatments decreased saturated and polyunsaturated fatty acids in olive oil.
- Taxon
- oliveOlea europaeae1
- Treatment
- nitrogen treatmentse4
- Outcome
- saturated fatty acid and polyunsaturated fatty acidse4
- Direction
- decreasede4
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“impact of foliar spray of two nitrogen sources; urea (U) and nano-N on oil content and quality of olive cv. ‘Zard’ during two consecutive seasons were investigated”
e4“Monounsaturated fatty acid and the ratio of oleic acid to linoleic acid were increased by the nitrogen treatments, especially with nano-N2, whereas it decreased in the case of saturated fatty acid and polyunsaturated fatty acids”
Claim · model-written summary
Both fertilizer sources improved leaf mineral composition of olive.
- Taxon
- oliveOlea europaeae1
- Treatment
- both fertilizer sourcese5
- Outcome
- leaf mineral compositionse5
- Direction
- improvede5
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“impact of foliar spray of two nitrogen sources; urea (U) and nano-N on oil content and quality of olive cv. ‘Zard’ during two consecutive seasons were investigated”
e5“The application of both fertilizer sources improved the leaf mineral compositions as well as the oil quality such as free fatty acids, peroxide activity, K232 and K270 extinction coefficients, the chlorophyll and carotenoid pigments”
Claim · model-written summary
Both fertilizer sources improved olive oil quality indices: free fatty acids, peroxide activity, K232 and K270 extinction coefficients.
- Taxon
- oliveOlea europaeae1
- Treatment
- both fertilizer sourcese5
- Outcome
- free fatty acids, peroxide activity, K232 and K270 extinction coefficientse5
- Direction
- improvede5
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“impact of foliar spray of two nitrogen sources; urea (U) and nano-N on oil content and quality of olive cv. ‘Zard’ during two consecutive seasons were investigated”
e5“The application of both fertilizer sources improved the leaf mineral compositions as well as the oil quality such as free fatty acids, peroxide activity, K232 and K270 extinction coefficients, the chlorophyll and carotenoid pigments”
Claim · model-written summary
Both fertilizer sources improved the chlorophyll and carotenoid pigments of olive oil.
- Taxon
- oliveOlea europaeae1
- Treatment
- both fertilizer sourcese5
- Outcome
- chlorophyll and carotenoid pigmentse5
- Direction
- improvede5
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“impact of foliar spray of two nitrogen sources; urea (U) and nano-N on oil content and quality of olive cv. ‘Zard’ during two consecutive seasons were investigated”
e5“The application of both fertilizer sources improved the leaf mineral compositions as well as the oil quality such as free fatty acids, peroxide activity, K232 and K270 extinction coefficients, the chlorophyll and carotenoid pigments”
Claim · model-written summary
Urea-sprayed olive trees had lower total phenolic content in their oil than nano-N-treated trees.
- Taxon
- olive treesOlea europaeae6
- Treatment
- ureae6
- Outcome
- Total phenolic content of the oile6
- Direction
- lowere6
- Comparator
- nano-Ne6
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e6“Total phenolic content of the oil in olive trees sprayed with urea was lower than those treated with nano-N”
Claim · model-written summary
Nano-N treatment gave high oil antioxidant capacity in olive trees.
- Taxon
- oliveOlea europaeae1
- Treatment
- nano-Ne7
- Outcome
- oil antioxidant capacitye7
- Direction
- highe7
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“impact of foliar spray of two nitrogen sources; urea (U) and nano-N on oil content and quality of olive cv. ‘Zard’ during two consecutive seasons were investigated”
e7“the oil antioxidant capacity was high in those trees treated with nano-N”
Claim · model-written summary
The authors recommend nano-N2 treatment rather than urea as an effective approach to improve olive oil quality.
- Taxon
- oliveOlea europaeae1
- Treatment
- nan-N2 treatment rather than ureae2
- Outcome
- oil qualitye2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“impact of foliar spray of two nitrogen sources; urea (U) and nano-N on oil content and quality of olive cv. ‘Zard’ during two consecutive seasons were investigated”
e2“nano-fertilizer, especially nan-N2 treatment rather than urea, is an effective approach to improve oil quality”
The same questions in other papers
nitrogen · quality: oil · Olea europaea (common olive)Positive and negative results
3 papers in the same direction as this paper · 2 in the opposite direction
- no effect
- no effect
- positive
2 papers more in this group
See all 6 papers →fertilization · quality: oil · Olea europaea (common olive)Positive and negative results
10 papers in the same direction as this paper · 4 in the opposite direction · 1 reporting no difference from an alternative
- no effect
- no effect
- no effect
12 papers more in this group
See all 16 papers →fertilization · physiology: pigments · Olea europaea (common olive)Positive and negative results
15 papers in the same direction as this paper · 1 in the opposite direction
- negative
- positive
- positive
13 papers more in this group
See all 17 papers →nitrogen · quality: phytochemicals · Olea europaea (common olive)Results agree
1 paper in the same direction as this paper
- negative
nanoparticle · quality: phytochemicals · Olea europaea (common olive)Results agree
1 paper in the same direction as this paper
- positive
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.