Abstract
ABSTRACT Sunflower is a crop that has aroused the interest of farmers because of its adaptability to wide climatic conditions and for its use in biodiesel production. However, there are only a few studies on sunflower fertilization in alkaline soils. This study aimed to evaluate nitrogen (N) and phosphorus (P) fertilization in sunflower (Helianthus annuus L.) cultivated in alkaline soil. A field experiment was carried out in Baraúnas-RN, Brazil, in a Haplic Cambisol derived from calcareous rock, where the sunflower H-251 hybrid was cultivated. The treatments were a combination of four doses of N (30, 60, 90 and 120 kg ha-1) and four doses of P2O5 (30, 60, 90 and 120 kg ha-1). Sunflower growth and yield increased with the doses of N and P2O5. Doses of 30 kg ha-1 of N and 30 kg ha-1 of P2O5 were more economical, corresponding to grain yield of 2378 kg ha-1. Critical levels associated with these doses of N and P2O5 were 28.2 g kg-1 for N leaf content, 2.84 for P leaf content, and 6.75 mg dm-3 for soil available P extracted by Mehlich-1.
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Claims 8
Claim · model-written summary
Sunflower growth increased with nitrogen dose.
- Taxon
- Sunflower
Helianthus annuuse0 - Treatment
- doses of Ne0
- Outcome
- growthe0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Sunflower growth and yield increased with the doses of N and P2O5”
Claim · model-written summary
Sunflower yield increased with nitrogen dose.
- Taxon
- SunflowerHelianthus annuuse0
- Treatment
- doses of Ne0
- Outcome
- yielde0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Sunflower growth and yield increased with the doses of N and P2O5”
Claim · model-written summary
Sunflower growth increased with P2O5 dose.
- Taxon
- SunflowerHelianthus annuuse0
- Treatment
- P2O5e0
- Outcome
- growthe0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Sunflower growth and yield increased with the doses of N and P2O5”
Claim · model-written summary
Sunflower yield increased with P2O5 dose.
- Taxon
- SunflowerHelianthus annuuse0
- Treatment
- P2O5e0
- Outcome
- yielde0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Sunflower growth and yield increased with the doses of N and P2O5”
Claim · model-written summary
A combined 30 kg ha-1 N and P2O5 dose was more economical and yielded 2378 kg ha-1.
- Taxon
- sunflowerHelianthus annuust0
- Treatment
- 30 kg ha-1 of N and 30 kg ha-1 of P2O5e0
- Outcome
- grain yielde0
- Value
- 2378 kg ha-1e0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Doses of 30 kg ha-1 of N and 30 kg ha-1 of P2O5 were more economical, corresponding to grain yield of 2378 kg ha-1”
t0“sunflower”
Claim · model-written summary
Critical N leaf content at those doses was 28.2 g kg-1.
- Taxon
- sunflowerHelianthus annuust0
- Outcome
- N leaf contente0
- Value
- 28.2 g kg-1e0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Critical levels associated with these doses of N and P2O5 were 28.2 g kg-1 for N leaf content”
t0“sunflower”
Claim · model-written summary
Critical P leaf content at those doses was 2.84.
- Taxon
- sunflowerHelianthus annuust0
- Outcome
- P leaf contente0
- Value
- 2.84e0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“2.84 for P leaf content”
t0“sunflower”
Claim · model-written summary
Critical available soil P at those doses was 6.75 mg dm-3.
- Taxon
- sunflowerHelianthus annuust0
- Outcome
- soil available Pe0
- Value
- 6.75 mg dm-3e0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“6.75 mg dm-3 for soil available P extracted by Mehlich-1”
t0“sunflower”
The same questions in other papers
phosphorus · yield · Helianthus annuus (common sunflower)Results differ
78 papers in the same direction as this paper · 2 in the opposite direction
- no effect
- no effect
- positive
77 papers more in this group
See all 81 papers →phosphorus · growth · Helianthus annuus (common sunflower)Positive and negative results
31 papers in the same direction as this paper · 6 in the opposite direction
- negative
- negative
- negative
34 papers more in this group
See all 38 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.