Abstract
Abstract The objective of this research was to evaluate the technical feasibility of SPAD index in the diagnosis of N status in ‘Esmeralda’ peach. The field trial, with five N rates applied to the soil (0, 40, 80, 120 and 160 kg ha-1 of N as urea form) was conducted in a randomized block design with four replications. During the years 2014, 2015, 2016 and 2017, SPAD readings were carried out with a Minolta SPAD-502 chlorophyll meter, in the leaf middle part, in 40 leaves per plot. The leaf N content determination was performed in CHN-S Elemental Analyzer. SPAD index and leaf N content increased in a linear way in response to increasing N rates applied in soil. There was a positive linear correlation between SPAD index and N concentration in leaves (0.652; 0.756; 0.762 and 0.767, p<0.05). SPAD index can be used for nutritional N diagnosis purpose in peach when readings are taken between the 13th and 15th weeks after full bloom. In the range between 39 and 49, the SPAD index indicates the leaf N content is included in “normal” class (33 – 45 g kg-1) of agronomic interpretation for the States of Rio Grande do Sul and Santa Catarina, Brazil.
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Claims 5
Claim · model-written summary
Peach SPAD index rose linearly with soil nitrogen rate.
- Taxon
- peach
Prunus persicat0 - Treatment
- increasing N rates applied in soile0
- Outcome
- SPAD indexe0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“SPAD index and leaf N content increased in a linear way in response to increasing N rates applied in soil.”
t0“Spad index for diagnosis of nitrogen status in ‘Esmeralda’ peach”
Claim · model-written summary
Peach leaf nitrogen content rose linearly with soil nitrogen rate.
- Taxon
- peachPrunus persicat0
- Treatment
- increasing N rates applied in soile0
- Outcome
- leaf N contente0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“SPAD index and leaf N content increased in a linear way in response to increasing N rates applied in soil.”
t0“Spad index for diagnosis of nitrogen status in ‘Esmeralda’ peach”
Claim · model-written summary
SPAD index correlated positively and linearly with peach leaf nitrogen, with yearly correlations of 0.652, 0.756, 0.762 and 0.767.
- Taxon
- peachPrunus persicat0
- Compound
- Ne0
- Outcome
- SPAD indexe0
- Direction
- positivee0
- Value
- 0.652; 0.756; 0.762 and 0.767e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“There was a positive linear correlation between SPAD index and N concentration in leaves (0.652; 0.756; 0.762 and 0.767, p<0.05).”
t0“Spad index for diagnosis of nitrogen status in ‘Esmeralda’ peach”
Claim · model-written summary
SPAD can diagnose peach nitrogen status when measured 13 to 15 weeks after full bloom.
- Taxon
- peachPrunus persicae0
- Outcome
- nutritional N diagnosise0
- Value
- between the 13th and 15th weeks after full bloome0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“SPAD index can be used for nutritional N diagnosis purpose in peach when readings are taken between the 13th and 15th weeks after full bloom.”
Claim · model-written summary
SPAD values of 39 to 49 indicate normal peach leaf nitrogen of 33 to 45 g kg-1.
- Taxon
- peachPrunus persicat0
- Outcome
- leaf N contente0
- Value
- 39 and 49e0
- Qualifier
- 33 – 45 g kg-1e0
- Setting
- Rio Grande do Sul and Santa Catarina, Brazile0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“In the range between 39 and 49, the SPAD index indicates the leaf N content is included in “normal” class (33 – 45 g kg-1) of agronomic interpretation for the States of Rio Grande do Sul and Santa Catarina, Brazil.”
t0“Spad index for diagnosis of nitrogen status in ‘Esmeralda’ peach”
The same questions in other papers
nitrogen · nutrient: content · Prunus persica (peach)Positive and negative results
4 papers in the same direction as this paper · 5 in the opposite direction
- no effect
- no effect
- no effect
6 papers more in this group
See all 10 papers →nitrogen · physiology: pigments · Prunus persica (peach)Results agree
3 papers in the same direction as this paper
- positive
- positive
- 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.