Abstract
Water and nitrogen managements are both very important to increase crop yield. An experiment was carried out in split plot design to study the effects of urea types (normal urea and coated urea) and irrigation on soil and fertilizer nitrogen use in maize (Zea mays L.) field in 2006 and 2007. Irrigation was used as main plot, and urea types were used as split-plot. Two irrigation levels, no irrigation in the whole growth duration and 85 mm irrigation at the blister stage, were designed. There were five nitrogen treatments, which were no nitrogen used as control (N0), normal urea 75 kg N/ha (N1), normal urea 150 kg N/ha (N2), coated urea 75 kg N/ha (C1) and coated urea 150 kg N/ha (C2). The results showed that, at the same level of irrigation and nitrogen, the soil nitrogen contents of the treatments with coated urea (CU) applied were higher in 0~40 cm soil layers, but lower in deeper soil layers, than those with normal urea (NU) applied. Irrigation increased the nitrate losing, but the nitrate loss of CU was lower than those of NU. Using CU with irrigation could increase the nitrogen uptake by maize, and more nitrogen was transfered to grain. At the same nitrogen level, CU had higher N recovery efficiency but lower soil N dependent rate than NU. When applied with CU, the nitrogen release rate was lower and the nitrogen was quickly absorbed by maize, which reduced the risk of nitrogen loss and increased the use efficiency of soil and fertilizer nitrogen. These results suggest that coated urea combined with deficit irrigation should be applied for high yield and nitrogen use efficiency of maize on the North China Plain.
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Claims 13
Claim · model-written summary
Coated urea left more soil nitrogen at 0~40 cm than normal urea.
- Treatment
- coated urea (CU)e0
- Outcome
- soil nitrogen contentse0
- Direction
- highere0
- Qualifier
- 0~40 cm soil layerse0
- Comparator
- normal urea (NU)e0
Zea maysOrganisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the soil nitrogen contents of the treatments with coated urea (CU) applied were higher in 0~40 cm soil layers, but lower in deeper soil layers, than those with normal urea (NU) applied”
t0“maize”
Claim · model-written summary
Coated urea left less nitrogen in deeper soil layers than normal urea.
- Treatment
- coated urea (CU)e0
- Outcome
- soil nitrogen contentse0
- Direction
- lowere0
- Qualifier
- deeper soil layerse0
- Comparator
- normal urea (NU)e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the soil nitrogen contents of the treatments with coated urea (CU) applied were higher in 0~40 cm soil layers, but lower in deeper soil layers, than those with normal urea (NU) applied”
t0“maize”
Claim · model-written summary
Irrigation increased nitrate loss.
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Irrigation increased the nitrate losing”
t0“maize”
Claim · model-written summary
Coated urea had less nitrate loss than normal urea.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the nitrate loss of CU was lower than those of NU”
t0“maize”
Claim · model-written summary
Coated urea with irrigation increased maize nitrogen uptake.
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Using CU with irrigation could increase the nitrogen uptake by maize”
Claim · model-written summary
Coated urea with irrigation increased nitrogen transfer to grain.
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Using CU with irrigation could increase the nitrogen uptake by maize, and more nitrogen was transfered to grain”
Claim · model-written summary
Coated urea had higher nitrogen recovery efficiency than normal urea.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“CU had higher N recovery efficiency but lower soil N dependent rate than NU”
t0“maize”
Claim · model-written summary
Coated urea had a lower soil nitrogen dependent rate than normal urea.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“CU had higher N recovery efficiency but lower soil N dependent rate than NU”
t0“maize”
Claim · model-written summary
Coated urea released nitrogen more slowly.
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“When applied with CU, the nitrogen release rate was lower”
t0“maize”
Claim · model-written summary
Maize quickly absorbed nitrogen when coated urea was applied.
Not reportedComparatorDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“When applied with CU, the nitrogen release rate was lower and the nitrogen was quickly absorbed by maize”
Claim · model-written summary
Coated urea reduced the risk of nitrogen loss.
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“which reduced the risk of nitrogen loss”
e1“the soil nitrogen contents of the treatments with coated urea (CU) applied were higher in 0~40 cm soil layers, but lower in deeper soil layers, than those with normal urea (NU) applied”
t0“maize”
Claim · model-written summary
Coated urea increased soil and fertilizer nitrogen use efficiency.
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“increased the use efficiency of soil and fertilizer nitrogen”
e1“the soil nitrogen contents of the treatments with coated urea (CU) applied were higher in 0~40 cm soil layers, but lower in deeper soil layers, than those with normal urea (NU) applied”
t0“maize”
Claim · model-written summary
The authors recommend coated urea with deficit irrigation for high maize yield and nitrogen use efficiency.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“coated urea combined with deficit irrigation should be applied for high yield and nitrogen use efficiency of maize on the North China Plain”
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- negative
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See all 489 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.