Abstract
N management must be based on crop demand and supply capacity of the soil. A field experiment was conducted to analyze the effect of chlorophyll meter (SPAD meter) based N management on growth, productivity and agronomic N use efficiency of rice (cv. IR 36) in lateritic soil of India during the wet season of 2010 and 2011. The Experiment contained twelve N management treatments such as farmers’ fertilizer practice, one fixed time N management (FTNM), nine treatments of real time N management (RTNM), and one control. The RTNM is the combination of three SPAD threshold (SPAD: 34, 36 and 38) and three N levels (15, 25 and 35 kg ha-1) for top dressing when the SPAD value of rice leaf falls below the threshold. The grain yield of RTNM was in the range 93 to 105% as that of FTNM, but with lower N application rate. Among RTNM treatments, SPAD 36 with 35 and 25 kg N ha-1 top-dressing could save N fertilizer by 20 to 35% compared to FTNM without reducing grain yield. Agronomic N use efficiency can be increased at high yield level using SPAD meter based N management.
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Claims 6
Claim · model-written summary
Real-time nitrogen management yielded 93 to 105% of fixed-time management with less nitrogen applied.
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The grain yield of RTNM was in the range 93 to 105% as that of FTNM, but with lower N application rate”
t0“Rice”
Claim · model-written summary
Real-time nitrogen management used less nitrogen than fixed-time management.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The grain yield of RTNM was in the range 93 to 105% as that of FTNM, but with lower N application rate”
t0“Rice”
Claim · model-written summary
SPAD 36 with 35 kg N ha-1 top-dressing saved 20 to 35% nitrogen fertilizer versus fixed-time management without reducing grain yield.
- Taxon
- Rice
Oryza sativat0 - Treatment
- SPAD 36 with 35e0
- Outcome
- N fertilizere0
- Direction
- savee0
- Value
- 20 to 35%e0
- Comparator
- FTNMe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“SPAD 36 with 35 and 25 kg N ha-1 top-dressing could save N fertilizer by 20 to 35% compared to FTNM without reducing grain yield”
t0“Rice”
Claim · model-written summary
SPAD 36 with 25 kg N ha-1 top-dressing saved 20 to 35% nitrogen fertilizer versus fixed-time management.
- Taxon
- RiceOryza sativat0
- Treatment
- 25 kg N ha-1 top-dressinge0
- Outcome
- N fertilizere0
- Direction
- savee0
- Value
- 20 to 35%e0
- Comparator
- FTNMe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“SPAD 36 with 35 and 25 kg N ha-1 top-dressing could save N fertilizer by 20 to 35% compared to FTNM without reducing grain yield”
t0“Rice”
Claim · model-written summary
These SPAD 36 treatments did not reduce grain yield relative to fixed-time management.
- Taxon
- RiceOryza sativat0
- Treatment
- SPAD 36 with 35 and 25 kg N ha-1 top-dressinge0
- Outcome
- grain yielde0
- Direction
- without reducinge0
- Comparator
- FTNMe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“SPAD 36 with 35 and 25 kg N ha-1 top-dressing could save N fertilizer by 20 to 35% compared to FTNM without reducing grain yield”
t0“Rice”
Claim · model-written summary
SPAD-meter nitrogen management can increase agronomic nitrogen use efficiency at high yield.
- Taxon
- RiceOryza sativat0
- Treatment
- SPAD meter based N managemente0
- Outcome
- Agronomic N use efficiencye0
- Direction
- increasede0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Agronomic N use efficiency can be increased at high yield level using SPAD meter based N management”
t0“Rice”
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