Abstract
Ammonium sulfate and urea are main sources of nitrogen (N) for annual crop production in developing countries. Two greenhouse experiments were conducted using ammonium sulfate and urea as N sources for upland rice grown on a Brazilian Oxisol. The N rates used were 0, 50, 100, 150, 3000, and 400 kg N kg−1 of soil. Yield and yield components were significantly increased in a quadratic fashion with increasing N rate. Ammonium sulfate X urea interaction was significant for grain yield, shoot dry matter yield, panicle number, plant height and root dry weight, indicating a different response magnitude of these plant parameters to two sources of N. Based on regression equation, maximum grain yield was achieved with the application of 380 mg N kg−1 by ammonium sulfate and 271 mg N kg−1 by urea. Grain yield and yield components were reduced at higher rates of urea (>300 mg kg N) but these plant parameters’ responses to ammonium sulfate at higher rates was constant. In the intermediate N rate range (125 to 275 mg kg−1), urea was slightly better compared to ammonium sulfate for grain yield. Grain yield was significantly related with plant height, shoot dry weight, panicle number, grain harvest index and root dry weight. Hence, improving these plant characteristics by using appropriate soil and plant management practices can improve upland rice yield.
Abstract from the paper’s OpenAlex record; open copy licensed other-oa. 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 11
Claim · model-written summary
Increasing nitrogen rate raised yield and yield components quadratically.
- Taxon
- UPLAND RICE
Oryza sativat0 - Treatment
- increasing N ratee0
- Outcome
- Yield and yield componentse0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Yield and yield components were significantly increased in a quadratic fashion with increasing N rate”
t0“UPLAND RICE”
Claim · model-written summary
Ammonium sulfate and urea interacted significantly for grain yield, shoot dry matter yield and panicle number.
- Taxon
- UPLAND RICEOryza sativat0
- Treatment
- Ammonium sulfate X urea interactione0
- Outcome
- grain yield, shoot dry matter yield, panicle numbere0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Ammonium sulfate X urea interaction was significant for grain yield, shoot dry matter yield, panicle number, plant height and root dry weight”
t0“UPLAND RICE”
Claim · model-written summary
The source interaction was significant for plant height and root dry weight.
- Taxon
- UPLAND RICEOryza sativat0
- Treatment
- Ammonium sulfate X urea interactione0
- Outcome
- plant height and root dry weighte0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Ammonium sulfate X urea interaction was significant for grain yield, shoot dry matter yield, panicle number, plant height and root dry weight”
t0“UPLAND RICE”
Claim · model-written summary
Maximum grain yield occurred with 380 mg N kg−1 ammonium sulfate.
- Taxon
- UPLAND RICEOryza sativat0
- Treatment
- 380 mg N kg−1 by ammonium sulfatee0
- Outcome
- maximum grain yielde0
- Direction
- maximume0
- Value
- 380 mg N kg−1e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“maximum grain yield was achieved with the application of 380 mg N kg−1 by ammonium sulfate”
t0“UPLAND RICE”
Claim · model-written summary
Maximum grain yield occurred with 271 mg N kg−1 urea.
- Taxon
- UPLAND RICEOryza sativat0
- Treatment
- 271 mg N kg−1 by ureae0
- Outcome
- maximum grain yielde0
- Direction
- maximume0
- Value
- 271 mg N kg−1e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“maximum grain yield was achieved with the application of 380 mg N kg−1 by ammonium sulfate and 271 mg N kg−1 by urea”
t0“UPLAND RICE”
Claim · model-written summary
Higher urea rates reduced grain yield and yield components.
- Taxon
- UPLAND RICEOryza sativat0
- Treatment
- higher rates of urea (>300 mg kg N)e0
- Outcome
- Grain yield and yield componentse0
- Direction
- reducede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Grain yield and yield components were reduced at higher rates of urea (>300 mg kg N)”
t0“UPLAND RICE”
Claim · model-written summary
Rice parameter responses remained constant at higher ammonium sulfate rates.
- Taxon
- UPLAND RICEOryza sativat0
- Treatment
- ammonium sulfate at higher ratese0
- Outcome
- plant parameters’ responsese0
- Direction
- constante0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“these plant parameters’ responses to ammonium sulfate at higher rates was constant”
t0“UPLAND RICE”
Claim · model-written summary
Urea gave slightly higher grain yield than ammonium sulfate at intermediate rates.
- Taxon
- UPLAND RICEOryza sativat0
- Treatment
- ureae0
- Outcome
- grain yielde0
- Direction
- slightly bettere0
- Qualifier
- intermediate N rate range (125 to 275 mg kg−1)e0
- Comparator
- ammonium sulfatee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“In the intermediate N rate range (125 to 275 mg kg−1), urea was slightly better compared to ammonium sulfate for grain yield”
t0“UPLAND RICE”
Claim · model-written summary
Grain yield was significantly related to plant height, shoot dry weight and panicle number.
- Taxon
- UPLAND RICEOryza sativat0
- Organ / stage
- plant height, shoot dry weight, panicle numbere0
- Outcome
- Grain yielde0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Grain yield was significantly related with plant height, shoot dry weight, panicle number, grain harvest index and root dry weight”
t0“UPLAND RICE”
Claim · model-written summary
Grain yield was significantly related to harvest index and root dry weight.
- Taxon
- UPLAND RICEOryza sativat0
- Organ / stage
- grain harvest index and root dry weighte0
- Outcome
- Grain yielde0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Grain yield was significantly related with plant height, shoot dry weight, panicle number, grain harvest index and root dry weight”
t0“UPLAND RICE”
Claim · model-written summary
The authors recommend managing plant characteristics to improve upland rice yield.
- Taxon
- upland riceOryza sativae0
- Outcome
- using appropriate soil and plant management practicese0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“improving these plant characteristics by using appropriate soil and plant management practices can improve upland rice yield”
The same questions in other papers
ammonium sulfate · yield · Oryza sativa (rice)Positive and negative results
25 papers in the same direction as this paper · 3 in the opposite direction · 6 reporting no difference from an alternative
- positive
- no effect
- no effect
31 papers more in this group
See all 35 papers →nitrogen · yield · Oryza sativa (rice)Positive and negative results
1,802 papers in the same direction as this paper · 193 in the opposite direction · 49 reporting no difference from an alternative
- no effect
- negative
- no effect
2,041 papers more in this group
See all 2,045 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.