Yield response
Gross margin
g analysis
y
Guangdi Li
NSW Department of Primary Industries
Field experiments
Field experiments
 G
Graham Centre site (2011‐2014)
h C
i (2011 2014)
– Focused on nitrogen benefits of break crops to subsequent crops  Site at Paddock 45 (2012‐2015)
– Focused on weed management strategies using Focused on weed management strategies using
break crops
Graham Centre site
Graham Centre site
2011
Single break Break crops
Wheat+N
Double breaks Double
breaks Canola+N
Break crops
Control Wheat+N
2012
Wheat
Break crops
Break crops
Break crops
Canola
Wheat+N
Wh t N
Wheat‐N
 Break crops
p
– Lupins, Field pea
– Vetch and Pastures
Vetch and Pastures
– Canola
2013
Wheat
Wheat
Wheat
Wheat
Wheat+N
Wh t N
Wheat‐N
2014
Treatment
Wheat
5
Wheat
5
Wheat
3
Wheat
3
Wheat+N
1
Wh t N
Wheat‐N
1
 Crop management
p
g
– Brown manured
– Hay cut
Hay cut
– Grain harvested
Site at Paddock 45
Site at Paddock 45
2012
Weed management
2013
Wheat
Weeds free Canola
Crop desicated
Crop desicated
Wheat
Break crops Brown manured Canola
Weeds present
Crop desicated
Wheat
Brown manured
d Canola
l
2014
Wheat
Wheat
Wheat
Wheat
Wheat
Wheat
h
2015
Wheat
Wheat
Wheat
Wheat
Wheat
Wheat
h
 Break crops: Canola, lupin, field pea and pastures
g
p
 Weed management: Weed free vs. Weed present
Rainfall
2011
2012
2013
2014
LTAR
Total
664
561
391
458
529
GSR
318
188
257
268
331
Yield response under single break
Yield response under single break
Year 1
2011
Pea
Year 2
2012 Wheat
Vetch
Wheat
Pasture Wheat
Lupin
Wheat
Canola
Wheat+N Wheat+N
Wheat‐N
Years 3&4
2013&14
Wheat
Wheat
Wheat
Wheat
Wheat
Wheat
Wheat
Wheat
Wheat+N
Wheat‐N
Crop
p
Year 1
Management Grain
2.5
BM
Significance
Hay cut
BM
Significance
Hay cut
BM
Si ifi
Significance
Grain
2.0
Grain
Significance
Grain
5.2
Grain
Significance
Year 2
Year 3
Grain (t/ha)
3.5
3.5
3.7
4.2
P= 0.055
n.s.
3.4
3.6
3.7
3.8
n.s.
n.s.
3.0
3.4
3.6
3.7
P 0 01
P= 0.01
n.s.
3.4
3.6
2.1
3.9
NA
N.A.
P< 0 05
P< 0.05
3.5
3.6
2.4
3.1
P< 0 05 P< 0.05
P< 0.05
P< 0 05
Year4
3.5
3.5
3.5
3.6
n.s.
3.4
3.3
n.s.
3.5
3.4
ns
n.s.
3.4
3.4
ns
n.s.
Yield response under single break
Yield response under single break
Crop
Management B.Manured Hay cut
Grain
Year 1
Year
1
2011
Pea
V t h
Vetch
Pasture
Vetch
Pasture
Pea
Lupin
Year 2
Year
2
2012
Wheat
Wh t
Wheat
Wheat
Wheat
Wheat
Wheat
Wheat
Years 3&4
Years
3&4 Year
Year 1
1 Year 2
Year 2
Year 3 Year 4
Year 3
Year 4
2013&2014
Grain (t/ha)
Wheat
3.7
4.2
3.5
Wh t
Wheat
37
3.7
38
3.8
36
3.6
Wheat
3.6
3.7
3.3
Significance
n.s.
P= 0.054 n.s.
Wheat
3.4
3.6
3.5
Wheat
3.0
3.4
3.4
Significance
P= 0.056 P< 0.01
Wheat
2.4
3.5
3.5
3.5
Wheat
2.1
3.4
3.6
3.5
Significance
g
N.A.
n.s.
n.s.
n.s.
Yield response under double breaks
Yield response under double breaks
Year 1
2011
Pea
Year 2
2012 Canola
Pasture Canola
Lupin
Wheat
Canola
Wheat+N Wheat+N
Wheat‐N
Years 3&4
2013&14
Wheat
Wheat
Wheat
Wheat
Wheat
Wheat
Wheat+N
Wheat‐N
Crop
Year 1
Management Grain
2.5
BM
Si ifi
Significance
Hay cut
BM
Significance
Grain
2.0
Grain
Significance
Grain
5.2
Grain
Significance
g
Year 2
Year 3
Grain (t/ha)
2.0
3.7
2.3
3.7
n.s.
n.s.
1.8
3.7
2.3
3.7
P< 0 05
P< 0.05
ns
n.s.
3.4
3.6
2.1
3.9
N.A.
P< 0.05
P< 0.05
3.5
3.6
2.4
3.1
P< 0.05 P< 0.05
Year4
3.5
3.4
n.s.
3.4
3.4
ns
n.s.
3.5
3.4
n.s.
3.4
3.4
n.s.
Yield response under double breaks
Yield response under double breaks
Crop
Year 1
Management 2011
B.Manured a u ed
Pea
ea
Pasture
Grain
Pea
Lupin
Year 2
2012
Canola
Ca
oa
Canola
Years 3&4 Year 1 Year 2 Year 3 Year 4
2013&2014 Grain (t/ha)
Wheat
eat
2.3
3
3.7
3
3.4
3
Wheat
2.3
3.7
3.4
Significance n.s.
n.s.
n.s.
Canola Wheat
27
2.7
20
2.0
37
3.7
35
3.5
Canola Wheat
2.0
2.1
3.9
3.4
Significance N.A.
n.s.
n.s.
n.s.
Soil mineral N at sowing
Soil mineral N at sowing
Year 1 2011
2011 Pea
Year 2
2012
2012 Wheat
Year 3
2013
Wheat
Wheat
Crop
Year 1
Management
Management Grain
94.7
BM
94.7
Significance
Significance NA
N.A.
Vetch
Wheat
Wheat
Hay cut
94.7
Wheat
BM
94.7
Si ifi
Significance NA
N.A.
Pasture Wheat
Wheat
Hay cut
94.7
Wheat
BM
94.7
Significance N.A.
Lupin
Wheat
Wheat
Grain
94.7
Canola
Wheat
Grain
94.7
Significance N.A.
Wheat+N Wheat+N Wheat+N Grain
94.7
Wheat‐N Wheat‐N Grain
Significance Year 2 Year 3
83.0
50.4
125.1 73.9
P<0 05 n.s.
P<0.05
ns
67.2
60.9
114.8 106.9
n.s. P<0.05
P 0 05
67.7
60.8
83.5
63.2
n.s.
n.s.
81.0
79.2
72.1
77.6
n.s.
n.s.
73.6
89.5
43 4
43.4
P<0.01
Gross margin analysis
Gross margin analysis
Crop Management
B.Manured d
Hay
Grain
Grain
Treatment
Pea
Vetch
Pasture
Vetch
Pasture
Pea
Lupin
Canola
+N
‐N
Income
$
$585
$553
$562
$825
$811
$714
$716
$859
$878
$
$663
Variable cost
$
$296
$295
$287
$400
$402
$354
$339
$359
$412
$
$333
Gross margin
$
$289
$259
$275
$425
$409
$360
$376
$500
$467
$
$330
((averaged
g across 3 years
y
with single
g break crop)
p)
Take home messages
Take home messages
 B
Brown manured treatments increased wheat yield d
i
d h
i ld
significantly due to additional N input
 The N benefit from pulses and pastures was greater than, or equivalent to 75 kg N/ha
 The N benefit from break crops diminished in the 2nd and 3rd wheat crops
p
Take home messages
Take home messages
 A
Averaged across 4 years, the rotation with canola d
4
h
i
ih
l
had the highest gross margin ($500/year)
 Treatments that were brown manured had the lowest gross margin ($259 ‐ $289/year) due to total loss of income in year 1 g
 However, brown manured treatments offer great opportunities to manage herbicide resistant weeds and reduce the risk of diseases, as well as provide p
significant N benefits