Abstract
Evaluating the effects of N and K supply on grapevines ( Vitis vinifera L.) and the techniques for nutritional diagnosis is of great importance for fertigation management of this crop. This study evaluated the effects of N and K fertigation on the soluble concentrations of NO 3 – and K + in the petiole sap and on the leaf chlorophyll index in drip irrigated ‘Syrah’ grapevine (from 17 June 2013 to 25 Nov 2014). The treatments consisted of five levels of N (0, 15, 30, 60 and 120 kg ha –1 ) and K 2 O (0, 15, 30, 60 and 120 kg ha –1 ), combined in an incomplete 5 2 factorial scheme in 13 combinations and arranged in randomized blocks with four replications. We determined NO 3 – and K + concentrations in petiole sap, leaf chlorophyll index, grapevine cluster mass and number per plant, mean grapevine cluster mass, and phenolic composition. High NO 3 – concentrations contributed positively to grapevine yield; however, increased K+ concentrations caused a negative response of sap. For 120 kg N ha –1 rate, NO 3 – in the sap and chlorophyll index showed higher values at the flowering stage, while high values for K + were observed during the grape-ripening stage.
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Claims 5
Claim · model-written summary
Higher sap nitrate concentrations contributed positively to grapevine yield.
VitisOrganisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“High NO 3 – concentrations contributed positively to grapevine yield”
Claim · model-written summary
Increased K+ concentration caused a negative sap response.
Not reportedTaxon
Verbatim
e0“increased K+ concentrations caused a negative response of sap.”
Claim · model-written summary
At 120 kg N ha –1, sap nitrate was higher at flowering.
- Organ / stage
- flowering stagee0
- Treatment
- 120 kg N ha –1 ratee0
- Outcome
- NO 3 – in the sape0
- Direction
- highere0
Not reportedTaxonComparator
Verbatim
e0“For 120 kg N ha –1 rate, NO 3 – in the sap and chlorophyll index showed higher values at the flowering stage”
Claim · model-written summary
At 120 kg N ha –1, chlorophyll index was higher at flowering.
- Organ / stage
- flowering stagee0
- Treatment
- 120 kg N ha –1 ratee0
- Outcome
- chlorophyll indexe0
- Direction
- highere0
Not reportedTaxonComparator
Verbatim
e0“For 120 kg N ha –1 rate, NO 3 – in the sap and chlorophyll index showed higher values at the flowering stage”
Claim · model-written summary
Sap K+ values were high during grape ripening.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“high values for K + were observed during the grape-ripening stage.”
t0“grapevines”
The same questions in other papers
nitrogen · physiology: pigments · VitisPositive and negative results
8 papers in the same direction as this paper · 3 in the opposite direction
- negative
- negative
- negative
8 papers more in this group
See all 12 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.