Abstract
Accurate nitrogen (N) fertilization and optimum plant density increase crop yields. In this study, I report the effects of N fertilization rate and plant density on maize yield in a meta-analysis, by using observations from 15 studies conducted in Ethiopia since the 2000s for possible refinement of N fertilizer and plant density recommendations. I assessed the response of maize to different N rates ha−1 compared to the control using the yield response approach. Application of N fertilizer significantly increased maize yields by 31.5% - 65.9% compared to control. plant density increased maize yields by 42% - 72.4% compared to the control. The interaction effect of the N rate increased maize yields by 27.6% - 95.9%, with Plant density, 58.7% - 152% on loam soil, compared to control yield. The interaction effect of Plant density with soil type increased maize yields by 47% - 108% on loam soil. In conclusion, the grain yield of maize increased with increasing N rate and plant density up to the optimum. Therefore, it’s possible to recommend using a high N rate with both low and medium plant density (< 45,000 plants ha-1) and (45,000 to 65,000plants ha-1) to harvest high grain yield.
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Claims 7
Claim · model-written summary
Nitrogen fertilizer increased maize yields by 31.5% to 65.9% versus control.
- Treatment
- N fertilizere0
- Outcome
- maize yieldse0
- Direction
- increasede0
- Value
- 31.5% - 65.9%e0
- Comparator
- controle0
Zea maysOrganisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Application of N fertilizer significantly increased maize yields by 31.5% - 65.9% compared to control.”
Claim · model-written summary
Higher plant density increased maize yields by 42% to 72.4% versus control.
- Treatment
- plant densitye0
- Outcome
- maize yieldse0
- Direction
- increasede0
- Value
- 42% - 72.4%e0
- Comparator
- controle0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“plant density increased maize yields by 42% - 72.4% compared to the control.”
Claim · model-written summary
The interaction effect of nitrogen rate increased maize yields by 27.6% to 95.9% versus control.
- Treatment
- N ratee0
- Outcome
- maize yieldse0
- Direction
- increasede0
- Value
- 27.6% - 95.9%e0
- Comparator
- control yielde0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The interaction effect of the N rate increased maize yields by 27.6% - 95.9%, with Plant density, 58.7% - 152% on loam soil, compared to control yield.”
Claim · model-written summary
The plant-density interaction increased maize yields by 58.7% to 152% on loam soil versus control.
- Treatment
- Plant densitye0
- Outcome
- maize yieldse0
- Direction
- increasede0
- Value
- 58.7% - 152%e0
- Comparator
- control yielde0
- Setting
- loam soile0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The interaction effect of the N rate increased maize yields by 27.6% - 95.9%, with Plant density, 58.7% - 152% on loam soil, compared to control yield.”
Claim · model-written summary
The interaction of plant density and soil type increased maize yields by 47% to 108% on loam soil.
- Treatment
- Plant density with soil typee0
- Outcome
- maize yieldse0
- Direction
- increasede0
- Value
- 47% - 108%e0
- Setting
- loam soile0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The interaction effect of Plant density with soil type increased maize yields by 47% - 108% on loam soil.”
Claim · model-written summary
Maize grain yield rose as nitrogen rate and plant density increased up to an optimum.
- Treatment
- increasing N rate and plant densitye0
- Outcome
- grain yielde0
- Direction
- increasede0
- Qualifier
- up to the optimume0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the grain yield of maize increased with increasing N rate and plant density up to the optimum.”
Claim · model-written summary
The author recommends high nitrogen rates with low or medium plant density to obtain high grain yield.
- Treatment
- high N rate with both low and medium plant densitye0
- Outcome
- high grain yielde0
- Qualifier
- (< 45,000 plants ha-1) and (45,000 to 65,000plants ha-1)e0
Not reportedTaxon
Verbatim
e0“recommend using a high N rate with both low and medium plant density (< 45,000 plants ha-1) and (45,000 to 65,000plants ha-1) to harvest high grain yield.”
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