Abstract
Seeding rate and N application strategies have been extensively researched for drill‐seeded, delayed flood rice ( Oryza sativa L.) production in the midsouthern United States. However, little economic analysis has been performed to determine the effects of seeding rate and N fertilization strategies on high‐yielding, lodging susceptible rice cultivars. The purpose of this research was to determine the effect of multiple N fertilization strategies and seeding rates on rice lodging and grain yield and use the data to determine optimal rice management practices based on evaluation of economic returns. Studies were established in Louisiana and Mississippi during the 2010 and 2012 growing seasons. Rice was drilled at seeding rates of 161, 323, and 483 seeds m −2 . Rice was fertilized with N at multiple rates and timings, representing recommended strategies as well as strategies designed to reduce lodging. Lodging and grain yield data were collected and used to determine net returns at high and low rice and N prices. Rice grain yield and net returns were maximized at a seeding rate of 323 seeds m −2 . Splitting N application between early‐season (V3) and late‐season (R1 or R3) applications decreased lodging, but resulted in decreased grain yield compared to optimal rates of N applied at V3. The 202 kg N ha −1 applied early‐season (V3) N fertilization strategy maximized both grain yield and net returns, despite relatively high levels of lodging. Optimal N fertilization during early‐vegetative growth appears to be necessary to maximize yield potential in this rice production system. Core Ideas Split N application in rice limits lodging but also reduce grain yield. High N rates and seeding rates increase lodging and harvest costs. Appropriate early‐season (preflood) N is necessary to maximize rice grain yield.
Abstract from the paper’s OpenAlex record; open copy licensed cc-by-nc-nd. 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 7
Claim · model-written summary
Rice grain yield and net returns were maximized at a seeding rate of 323 seeds m −2.
- Taxon
- Rice
Oryza sativae1 - Treatment
- seeding rate of 323 seeds m −2e1
- Outcome
- grain yield and net returnse1
- Direction
- maximizede1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“Rice grain yield and net returns were maximized at a seeding rate of 323 seeds m −2”
Claim · model-written summary
Splitting N application between early-season (V3) and late-season (R1 or R3) applications decreased rice lodging.
- Taxon
- RiceOryza sativat0
- Treatment
- Splitting N application between early‐season (V3) and late‐season (R1 or R3) applicationse2
- Outcome
- lodginge2
- Direction
- decreasede2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Affect Rice Lodging”
e2“Splitting N application between early‐season (V3) and late‐season (R1 or R3) applications decreased lodging, but resulted in decreased grain yield compared to optimal rates of N applied at V3”
Claim · model-written summary
Splitting N application between early-season and late-season applications decreased rice grain yield compared with optimal rates of N applied at V3.
- Taxon
- RiceOryza sativat0
- Treatment
- Splitting N application between early‐season (V3) and late‐season (R1 or R3) applicationse2
- Outcome
- grain yielde2
- Direction
- decreasede2
- Comparator
- optimal rates of N applied at V3e2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Affect Rice Lodging”
e2“Splitting N application between early‐season (V3) and late‐season (R1 or R3) applications decreased lodging, but resulted in decreased grain yield compared to optimal rates of N applied at V3”
Claim · model-written summary
The 202 kg N ha −1 early-season (V3) N fertilization strategy maximized rice grain yield and net returns.
- Taxon
- RiceOryza sativat0
- Treatment
- 202 kg N ha −1 applied early‐season (V3) N fertilization strategye3
- Outcome
- grain yield and net returnse3
- Direction
- maximizede3
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Affect Rice Lodging”
e3“The 202 kg N ha −1 applied early‐season (V3) N fertilization strategy maximized both grain yield and net returns, despite relatively high levels of lodging”
Claim · model-written summary
Rice lodging was relatively high under the 202 kg N ha −1 early-season (V3) N fertilization strategy.
- Taxon
- RiceOryza sativat0
- Treatment
- 202 kg N ha −1 applied early‐season (V3) N fertilization strategye3
- Outcome
- lodginge3
- Qualifier
- relatively high levelse3
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Affect Rice Lodging”
e3“The 202 kg N ha −1 applied early‐season (V3) N fertilization strategy maximized both grain yield and net returns, despite relatively high levels of lodging”
Claim · model-written summary
High N rates and high seeding rates increased rice lodging and harvest costs.
- Taxon
- RiceOryza sativat0
- Treatment
- High N rates and seeding ratese4
- Outcome
- lodging and harvest costse4
- Direction
- increasee4
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Affect Rice Lodging”
e4“High N rates and seeding rates increase lodging and harvest costs”
Claim · model-written summary
Optimal early-vegetative N fertilization appears necessary to maximize rice yield potential in this production system.
- Taxon
- riceOryza sativae5
- Treatment
- Optimal N fertilization during early‐vegetative growthe5
- Outcome
- maximize yield potentiale5
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e5“Optimal N fertilization during early‐vegetative growth appears to be necessary to maximize yield potential in this rice production system”
The same questions in other papers
density · yield · Oryza sativa (rice)Positive and negative results
329 papers in the same direction as this paper · 58 in the opposite direction · 7 reporting no difference from an alternative
- no effect
- positive
- positive
391 papers more in this group
See all 395 papers →nitrogen · growth · Oryza sativa (rice)Positive and negative results
401 papers in the same direction as this paper · 101 in the opposite direction · 8 reporting no difference from an alternative
- positive
- negative
- negative
507 papers more in this group
See all 511 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
- negative
- no effect
- positive
2,041 papers more in this group
See all 2,045 papers →fertilization · yield · Oryza sativa (rice)Positive and negative results
3,182 papers in the same direction as this paper · 207 in the opposite direction · 65 reporting no difference from an alternative
- no effect
- positive
- no effect
3,451 papers more in this group
See all 3,455 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.