Wheat Nitrogen Diagnosticsin the Yaqui Valley
OBJECTIVE
• To develop diagnostic tools that will help farmers apply the optimum economic nitrogen rate in wheat.
• To transfer this knowledge intensive technology into farmers’ fields.
On-farm Nitrogen x Variety Trials Y00-01
Location (Block)
Gra
in y
ield
(kg
/ha
) a
t 1
2%
mo
istu
re
4000
5000
6000
7000
8000 0 125 F 125 N 250
1603 710 814
On Farm Trials Year 2001-2002
Location
Gra
in y
ield
at 1
2%
moi
stu
re (
kg/h
a)
4500
5000
5500
6000
6500
7000
7500
75-0-25 125 kgN/ha0-33-66 125 kgN/ha 0-33-33 250 kgN/ha 0 kgN/ha
Block 612 Block 812
2000300040005000600070008000
1 2 3 4 5 6 7 8 9 10 11 12 13 14
N rate (kgN/ha)
Gra
in Y
ield
(kg/
ha)
194
142 250
100 125
125
125125
250
250
00
On-farm Trials 2002-2003
NDVI
N richStrip
N rate Experiment
Area Fertilized According to the Sensor
N Rich Strip N Deficient Area
NDVI = 0.65 NDVI = 0.31
Yield Potential
300N 0N
246 kgN/ha6831kg
Vs123 kgN/ha
7068kg
Manuel Lopez de Lara
No YieldDifference0 vs 300N
300 N 0N
Don Melquiades
300 kgN/haVs
180 kgN/ha
No Yield Difference
Cesar Valenzuela
11 tons Chicken ManureVs.
20 tons Chicken Manure
No Yield Difference
Union Cajeme
Insisted in 150 kg N moreOver the 11 tons Chicken Manure
Technical Adviser called me and asked me if I was making
that recommendation
Farmer Basal N rate N rate Experiment
SensorRec.
C.Valenzuela 135 N No response 0
L.A. Amaya 150 N No response 0
S. Dabdub 175 N No response 0
J. Castro 100 N No response 0
E. Pablos 0 N 200 N 0
M. Lopez de Lara
150N No response 0
J. Felix Sacos No response 0
E. Olea 100N Lost 0
On-farm Trials for Validation of theSensor
N RichStrip
N RichStrip
300N 0N
246 kgN/ha6831kg
Vs123 kgN/ha
7068kg
Manuel Lopez de Lara
No YieldDifference0 vs 300N
