Abstract
Planting at an optimum density and supplying adequate nitrogen (N) to achieve higher yields is a common practice in crop production, especially for maize (Zea mays L.); however, excessive N fertilizer supply in maize production results in reduced N use efficiency (NUE) and severe negative impacts on the environment. This research was conducted to determine the effects of increased plant density and reduced N rate on grain yield, total N uptake, NUE, leaf area index (LAI), intercepted photosynthetically active radiation (IPAR), and resource use efficiency in maize. Field experiments were conducted using a popular maize hybrid Zhengdan 958 (ZD958) under different combinations of plant densities and N rates to determine an effective approach for maize production with high yield and high resource use efficiency. Increasing plant density was clearly able to promote N absorption and LAI during the entire growth stage, which allowed high total N uptake and interception of radiation to achieve high dry matter accumulation (DMA), grain yield, NUE, and radiation use efficiency (RUE). However, with an increase in plant density, the demand of N increased along with grain yield. Increasing N rate can significantly increase the DMA, grain yield, LAI, IPAR, and RUE. However, this increase was non-linear and due to the input of too much N fertilizers, the efficiency of N use at NCK (320 kg ha−1) was low. An appropriate reduction in N rate can therefore lead to higher NUE despite a slight loss in grain production. Taking into account both the need for high grain yield and resource use efficiency, a 30% reduction in N supply, and an increase in plant density of 3 plants m−2, compared to LD (5.25 plants m−2), would lead to an optimal balance between yield and resource use efficiency.
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 9
Claim · model-written summary
Higher plant density promoted maize N absorption and leaf area index.
Zea maysNot reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Increasing plant density was clearly able to promote N absorption and LAI during the entire growth stage”
t0“maize”
Claim · model-written summary
Higher plant density raised total N uptake and radiation interception.
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“which allowed high total N uptake and interception of radiation”
t0“plant density and reduced N rate lead to more grain yield and higher resource utilization in summer maize”
Claim · model-written summary
Higher density raised dry matter accumulation, grain yield, NUE and radiation use efficiency.
- Treatment
- plant densityt0
- Outcome
- dry matter accumulation (DMA), grain yield, NUE, and radiation use efficiency (RUE)e0
- Direction
- highe0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“to achieve high dry matter accumulation (DMA), grain yield, NUE, and radiation use efficiency (RUE)”
t0“plant density and reduced N rate lead to more grain yield and higher resource utilization in summer maize”
Claim · model-written summary
N demand increased with density alongside grain yield.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“with an increase in plant density, the demand of N increased along with grain yield”
t0“maize”
Claim · model-written summary
Increasing N rate significantly increased dry matter accumulation, grain yield and LAI.
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Increasing N rate can significantly increase the DMA, grain yield, LAI”
t0“maize”
Claim · model-written summary
Increasing N rate significantly increased IPAR and RUE.
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Increasing N rate can significantly increase the DMA, grain yield, LAI, IPAR, and RUE”
t0“maize”
Claim · model-written summary
N use efficiency at NCK was low at 320 kg ha−1.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the efficiency of N use at NCK (320 kg ha−1) was low”
t0“maize”
Claim · model-written summary
Reducing N rate increased NUE despite a slight loss in grain production.
- Treatment
- reduction in N ratee0
- Outcome
- NUEe0
- Direction
- highere0
- Qualifier
- despite a slight loss in grain productione0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“An appropriate reduction in N rate can therefore lead to higher NUE despite a slight loss in grain production”
t0“maize”
Claim · model-written summary
The authors recommend a 30% N reduction and 3 plants m−2 density increase versus LD to balance yield and resource efficiency.
- Treatment
- a 30% reduction in N supply, and an increase in plant density of 3 plants m−2e0
- Outcome
- optimal balance between yield and resource use efficiencye0
- Comparator
- LDe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“a 30% reduction in N supply, and an increase in plant density of 3 plants m−2, compared to LD (5.25 plants m−2), would lead to an optimal balance between yield and resource use efficiency”
t0“maize”
The same questions in other papers
density · nutrient: content · Zea mays (maize)Positive and negative results
33 papers in the same direction as this paper · 10 in the opposite direction
- positive
- no effect
- negative
40 papers more in this group
See all 44 papers →nitrogen · physiology: photosynthesis · Zea mays (maize)Positive and negative results
77 papers in the same direction as this paper · 18 in the opposite direction · 2 reporting no difference from an alternative
- positive
- negative
- negative
94 papers more in this group
See all 98 papers →density · growth · Zea mays (maize)Positive and negative results
118 papers in the same direction as this paper · 76 in the opposite direction · 2 reporting no difference from an alternative
- positive
- positive
- positive
193 papers more in this group
See all 197 papers →density · yield · Zea mays (maize)Positive and negative results
518 papers in the same direction as this paper · 132 in the opposite direction · 7 reporting no difference from an alternative
- positive
- positive
- positive
654 papers more in this group
See all 658 papers →nitrogen · yield · Zea mays (maize)Positive and negative results
1,905 papers in the same direction as this paper · 234 in the opposite direction · 45 reporting no difference from an alternative
- positive
- positive
- positive
2,181 papers more in this group
See all 2,185 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.