Abstract
With the advent of precision guidance systems, maize ( Zea mays L.) farmers in various tillage systems have more options in pre‐plant nutrient banding relative to the intended crop rows. Anhydrous ammonia (NH 3 ) placement during pre‐plant application is of interest because of concerns for possible ammonia toxicity to maize seedlings when high NH 3 rates are applied too close to the seed row and the need to improve plant‐nitrogen (N) use efficiencies. Field studies were conducted between 2010 and 2012 near West Lafayette, IN, to compare traditional angled (diagonally) vs. precision‐guided parallel NH 3 applications (the latter was offset 15 cm from the future row) in no‐till and conventional tillage systems. The NH 3 was injected to depths of about 12 cm at N rates of 145 and 202 kg N ha −1 . Maize was planted with additional starter N (20 kg N ha −1 ) within 6 d of NH 3 application. Neither NH 3 application placement resulted in significant maize seedling mortality. Conventional tillage increased mean grain yields across N rates and placement treatments from 10.6 to 11.6 Mg ha −1 . Tillage did not impact reproductive‐stage leaf chlorophyll content (SPAD), or whole‐plant N content at maturity when NH 3 was parallel applied, but these plant responses were significantly lower in no‐till after diagonal application. Lowering the pre‐plant N rate to 145 from 202 kg N ha −1 significantly lowered maize whole‐plant biomass and N accumulation at maturity with diagonal application, but not when NH 3 was parallel applied.
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 10
Claim · model-written summary
Neither ammonia placement produced significant maize seedling mortality.
Zea maysNot reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Neither NH 3 application placement resulted in significant maize seedling mortality.”
Claim · model-written summary
Conventional tillage increased mean grain yield from 10.6 to 11.6 Mg ha −1.
- Treatment
- Conventional tillagee0
- Outcome
- mean grain yieldse0
- Direction
- increasede0
- Value
- 11.6 Mg ha −1e0
- Qualifier
- 10.6e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Conventional tillage increased mean grain yields across N rates and placement treatments from 10.6 to 11.6 Mg ha −1 .”
t0“maize ( Zea mays L.)”
Claim · model-written summary
Tillage did not affect reproductive‐stage leaf chlorophyll content (SPAD) with parallel ammonia placement.
- Treatment
- Tillagee0
- Outcome
- reproductive‐stage leaf chlorophyll content (SPAD)e0
- Direction
- did not impacte0
- Qualifier
- NH 3 was parallel appliede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Tillage did not impact reproductive‐stage leaf chlorophyll content (SPAD), or whole‐plant N content at maturity when NH 3 was parallel applied, but these plant responses were significantly lower in no‐till after diagonal application.”
t0“maize ( Zea mays L.)”
Claim · model-written summary
No till had lower reproductive‐stage leaf chlorophyll content (SPAD) after diagonal ammonia placement.
- Treatment
- no‐tille0
- Outcome
- reproductive‐stage leaf chlorophyll content (SPAD)e0
- Direction
- lowere0
- Qualifier
- diagonal applicatione0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Tillage did not impact reproductive‐stage leaf chlorophyll content (SPAD), or whole‐plant N content at maturity when NH 3 was parallel applied, but these plant responses were significantly lower in no‐till after diagonal application.”
t0“maize ( Zea mays L.)”
Claim · model-written summary
Tillage did not affect whole‐plant N content at maturity with parallel ammonia placement.
- Treatment
- Tillagee0
- Outcome
- whole‐plant N content at maturitye0
- Direction
- did not impacte0
- Qualifier
- NH 3 was parallel appliede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Tillage did not impact reproductive‐stage leaf chlorophyll content (SPAD), or whole‐plant N content at maturity when NH 3 was parallel applied, but these plant responses were significantly lower in no‐till after diagonal application.”
t0“maize ( Zea mays L.)”
Claim · model-written summary
No till had lower whole‐plant N content at maturity after diagonal ammonia placement.
- Treatment
- no‐tille0
- Outcome
- whole‐plant N content at maturitye0
- Direction
- lowere0
- Qualifier
- diagonal applicatione0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Tillage did not impact reproductive‐stage leaf chlorophyll content (SPAD), or whole‐plant N content at maturity when NH 3 was parallel applied, but these plant responses were significantly lower in no‐till after diagonal application.”
t0“maize ( Zea mays L.)”
Claim · model-written summary
Reducing nitrogen rate lowered maize whole‐plant biomass with diagonal ammonia placement.
- Treatment
- Lowering the pre‐plant N rate to 145 from 202 kg N ha −1e0
- Outcome
- maize whole‐plant biomasse0
- Direction
- lowerede0
- Qualifier
- diagonal applicatione0
- Comparator
- 202 kg N ha −1e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Lowering the pre‐plant N rate to 145 from 202 kg N ha −1 significantly lowered maize whole‐plant biomass and N accumulation at maturity with diagonal application, but not when NH 3 was parallel applied.”
Claim · model-written summary
Reducing nitrogen rate did not lower maize whole‐plant biomass with parallel ammonia placement.
- Treatment
- Lowering the pre‐plant N rate to 145 from 202 kg N ha −1e0
- Outcome
- maize whole‐plant biomasse0
- Direction
- note0
- Qualifier
- NH 3 was parallel appliede0
- Comparator
- 202 kg N ha −1e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Lowering the pre‐plant N rate to 145 from 202 kg N ha −1 significantly lowered maize whole‐plant biomass and N accumulation at maturity with diagonal application, but not when NH 3 was parallel applied.”
Claim · model-written summary
Reducing nitrogen rate lowered N accumulation at maturity with diagonal ammonia placement.
- Treatment
- Lowering the pre‐plant N rate to 145 from 202 kg N ha −1e0
- Outcome
- N accumulation at maturitye0
- Direction
- lowerede0
- Qualifier
- diagonal applicatione0
- Comparator
- 202 kg N ha −1e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Lowering the pre‐plant N rate to 145 from 202 kg N ha −1 significantly lowered maize whole‐plant biomass and N accumulation at maturity with diagonal application, but not when NH 3 was parallel applied.”
Claim · model-written summary
Reducing nitrogen rate did not lower N accumulation at maturity with parallel ammonia placement.
- Treatment
- Lowering the pre‐plant N rate to 145 from 202 kg N ha −1e0
- Outcome
- N accumulation at maturitye0
- Direction
- note0
- Qualifier
- NH 3 was parallel appliede0
- Comparator
- 202 kg N ha −1e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Lowering the pre‐plant N rate to 145 from 202 kg N ha −1 significantly lowered maize whole‐plant biomass and N accumulation at maturity with diagonal application, but not when NH 3 was parallel applied.”
The same questions in other papers
nitrogen · phenology · Zea mays (maize)Results differ
14 papers in the same direction as this paper · 29 in the opposite direction
- positive
- positive
- positive
40 papers more in this group
See all 44 papers →tillage · phenology · Zea mays (maize)Positive and negative results
9 papers in the same direction as this paper · 5 in the opposite direction
- positive
- positive
- positive
11 papers more in this group
See all 15 papers →tillage · physiology: pigments · Zea mays (maize)Positive and negative results
4 papers in the same direction as this paper · 15 in the opposite direction
- positive
- positive
- positive
16 papers more in this group
See all 20 papers →nitrogen · growth · Zea mays (maize)Positive and negative results
128 papers in the same direction as this paper · 619 in the opposite direction
- positive
- positive
- positive
744 papers more in this group
See all 748 papers →tillage · yield · Zea mays (maize)Positive and negative results
811 papers in the same direction as this paper · 230 in the opposite direction · 57 reporting no difference from an alternative
- negative
- no effect
- negative
1,095 papers more in this group
See all 1,099 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.