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MALLEE SUSTAINABLE FARMING
CORE TRIAL SITE RESULTS
WAIKERIE 2005
for more information visit www.msfp.org.au
Important information
Although Mallee Sustainable Farming Inc. (MSF) has taken all reasonable care in
preparing this advice, neither MSF nor its partner agencies accept any liability
resulting from the interpretation or use of the information set out in this document.
1
MSF Core Trial site Results – Waikerie 2005
David Roget, Bill Davoren and Gupta Vadakattu
Contents
1.
2.
3.
4.
5.
6.
7.
Summary
Rainfall
Available Soil water
Available Soil Nitrogen
Yield Potential and early growth
Grain Yield and Protein
Gross Margins
Appendices
1. Trial Plan
2. Soil Moisture Results
3. Soil Nitrogen Results
4. Additional Trials
1. Summary
•
•
•
•
•
•
•
Off-season rainfall of 125mm (Dec-Apr) was above average with most falling
in Dec-Jan with negligible rain through autumn until the break in June. Good
rains through the remainder of the growing season brought the GSR up to the
average of around 160mm
The good off-season rain was ideal for stubble breakdown, non-symbiotic N
fixation and net N mineralisation from the intensive cereal treatments yet was
not high enough for significant N leaching following the pasture or pulse
phases.
At sowing treatments had between 20-36 mm of available soil moisture stored
to 1m (approx 40-60% of the soils storage capacity) the bulk of this located at
20-60cm below the surface.
Soil Nitrogen levels after either pulses or pasture were very high at sowing
while after wheat N levels were lower but still adequate.
Yield potential at sowing was 1.6t/ha of wheat based on the available water
(stored soil moisture and average rainfall from sowing).
Final grain yields ranged from 2.0 to 2.4t/ha. The higher yields occurred in
the intensive cropping treatments and exceeded the recalculated potential
yields (using actual rainfall). The lower yields occurred in the district practice
pasture/wheat treatments.
After 8 years of the trial (which included 2 severe droughts) cumulative gross
margins were still highest following opportunity cropping ($1102/ha) and
compared favorably to the district practice wheat / pasture ($602/ha).
2. Rainfall
High early summer rain (80mm Dec04-Jan05) was followed by a very dry autumn. The
break to the season occurred in mid June, which allowed the sowing of the first plots. Very
good rainfall followed and despite a dry period in August the growing season rainfall
(Apr-Oct) reached 161mm a deficit of only 3mm on the average of 164mm. (Figure 1).
Total rainfall for the year was 261mm (Av. 252mm).
2
Figure1. Cumulative and average rainfall at the Waikerie Trial Site.
Cumulative Rainfall MSF Waikerie Core Site
300
Average
2003
2004
2005
200
150
100
50
0
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
3. Available Soil Water
At sowing there was between 20 and 36 mm of plant available water based on the residual
soil moisture measured from previous harvest sampling (Figure 2) and was largely a result
of the good opening rains. There was very little, if any, water stored from the Dec / Jan
rains. This amount of water is around 40-60% of the storage capacity of the soil in the root
zone and was primarily located around 40-60cm below the surface. In general, the various
rotation and tillage treatments have not a significant effect on available water at sowing at
the Waikerie site.
Figure 2. Available soil moisture at sowing in different rotations.
Waikerie Available Moisture at Sowing 2005
Volumetric moisture mm
0.00
2.00
4.00
6.00
8.00
10.00
12.00
0
20
Intensive Cropping
Depth cm
Cumulative Rainfall mm
250
40
26mm
60
80
100
28mm
30mm
Intensive Pulse/Wheat
District Practice
Pasture/Wheat
3
4. Available Soil Nitrogen
The average available N at sowing was 110 kg/ha, which was higher than usual and was
due to (i) increased mineralisation following above average off season rains of 124 mm
(average 100 mm) and (ii) low export of N as a result of the low yields from the 2004
drought. A larger proportion of the N was located deeper in the profile. This is particularly
the case in the pulse/wheat rotations where the off-season rains have gradually leached the
N down the profile where it may be less available (Figure 3).
High input treatments that included a legume in the rotation had the highest levels of
available N (134 kg/ha) compared to the district practice wheat / pasture treatments (95
kg/ha) or the high input intensive rotations with no legume component (79 kg/ha). Subsoil
constraints (salt and boron) at this site are only moderate but they still limit the uptake of
all the potentially available N. In general, for this site, the indicated available soil N needs
to be reduced by around 15 kg/ha to determine the amount of N the plants can access.
The above average off-season rainfall (Dec – Apr) would have been beneficial for N input from
non-symbiotic bacteria, particularly in the continuous cereal treatments. However more work is
required to better define the amount of N input in any given year and to show just when this
microbial N moves to the available or mineral N pool.
Figure 3. Available soil nitrogen in different rotations.
Waikerie Soil Nitrate at Sowing 2005
Nitrogen kg/ha
0
10
20
30
40
0
20
Depth cm
Intensive Cropping
40
Intensive Pulse/Wheat
District Practice
Pasture/Wheat
60
79 kg/ha
95 kg/ha
134 kg/ha
80
100
5. Yield Potential
Estimate at sowing
Based on 30 mm of available soil water at sowing and assuming an average rainfall from
sowing to October of 109mm, less an evaporation loss of 60 mm, the potential amount of
water for crop production is: (109+30) – 60 = 79 mm. That would give a potential yield of
approximately 1.6 t/ha (79mm x 20 kg/mm).
4
The N available at sowing was sufficient to meet this yield potential in all rotations; 64kg
N (1.6 t/ha X 40 kg/ha). For the high input non-legume treatments this N would come
from the soil 64 kg/ha available at sowing (79 - 15 unavailable at depth). N inputs of 21
kg/ha and additional N from in crop mineralisation (approx. 15 kg/ha) would provide for
higher N requirements that would be needed for a more favorable season.
Based on actual rainfall
The yield potential calculated on the actual rainfall from sowing to October (129mm) plus
the stored water at sowing less an evaporation loss of 60 mm means the potential amount
of water for crop production was: (129+30) – 60 = 99 mm. That would give a potential
yield of approximately 2 t/ha (99mm x 20 kg/mm).
6. Grain Yield and Protein
Although the break to the season was very late, above average rain for most of the
remaining growing season allowed many of the crops to reach and even exceed the
potential yield of 2 t/ha. Wheat yields were similar in the district practice treatments
following pasture (T 2,4) regardless of tillage treatment, both yielding 2 t/ha (Table 1).
Intensive wheat /pulse treatments (T 6, 7, 8) sown to Yitpi in 2004 and again in 2005
achieved yields between 2.1 and 2.2 t/ha while the opportunity cropping treatments (T10,
11) and sown to wheat for the 5th consecutive season yielded an average of 2.4 t/ha (var.
Clearfield Stiletto). The Clearfield Stiletto may have benefited from both (i) improved
grass weed control offered by the Midas herbicide and (ii) higher plant establishment
(Table 1) than the Yitpi treatments where plant numbers were lower than planned. The
yields of the intensive cereal (Clearfield Stiletto) were 20% above the calculated potential
yield (25kg/ha /mm water) and was the highest water use efficiency measured at the site to
date. This high efficiency is due to the low water stress from the benefits of the very mild
spring conditions and adequate soil nutrition to take advantage of the opportunity. The
previous highest water use efficiency (22 kg/ha/mm) also occurred with similar spring
conditions.
Kaspa peas (T 5) appeared to suffer from herbicide damage and yielded only 0.64 t/ha,
however in a separate trial at the Waikerie site Parafield peas achieved yields of up to 1.7
t/ha indicating the good potential for peas in the mallee given the right seasonal
conditions. However the risk associated with seasonal uncertainty indicate a limited role
for the pulse crops.
Canola (T 9) variety ATR Eyre looked good early in the season however a combination of
bud worm attack and later in the season a large amount of pod drop for reasons unknown
severely reduced the yield by an estimated 50% and only 0.6 t/ha was harvested.
Grain proteins were high (13.4% to14.5%) as expected due to the high levels of soil
nitrogen at sowing and good conditions for mineralisation during the spring (Table 1).
7. Gross Margins
The change in commodity and input prices over time has made accurate and meaningful
comparisons between treatments more difficult as time goes by. Two key issues that need
to be considered are:
1. The improvement in sheep prices and the very wide range of returns that can be
achieved on different soil types and with different management systems.
2. The dramatic impact wheat futures can have on profitability. For example wheat
could be locked in at $200/t in February 2005.
5
Gross margins are based on a 5-year average silo returns and input costs prior to the start
of the trial. Treatment gross margins varied from $ -39/ha for peas to $232/ha for low
input wheat after pasture (Table 1). Gross margins for pastures were calculated at an
average of $23/ha.
Cumulative gross margins after 8 years still show the opportunity cropping (T 11) highest
at $1145/ha compared to district practice wheat / pasture (average of T1+T2) at $620/ha.
Intensively cropped treatments with set cereal /pulse or cereal / canola treatments
performed the worst (average $455/ha) due to the large losses of the alternative crops in
poor seasons.
The performance of the opportunity cropping system has been very good, especially when
the average rainfall decile has been 4.5 over the last 8 seasons compared to the long term
average of 5.5 which is a reduction from the average of 20%.
6
Table 1. Waikerie Core Trial Results 2005
Treatment
Number
Rotation
Tillage Input
Level
1
2
3
4
5
6
7
8
9
10
11
Past / Wheat
Wheat / Past
Past / Wheat
Wheat / Past
Pulse / Wheat
Wheat /Wheat
Wheat/ Wheat
Wheat/ Wheat
Canola / Wheat
Wheat /Wheat
Wheat /Wheat
CC
CC
CC
DD
DD
CC
DD
DD
DD
DD
RT
LSD
(P=0.05)
* Historical Prices (5 year average)
DP
DP
High
DP
High
High
High
High
High
High
High
Emergence
(Plants/m2)
Anthesis
Biomass
(t/ha)
Grain
Yield
(t/ha)
Grain
Protein
(%)
1000
Grain
Wt (g)
122
3.00
2.01
13.6
39.9
2.86
1.98
0.64
2.17
2.06
2.14
0.60
2.42
2.29
14.0
24.4
14.5
13.4
14.2
38.4
35.4
36.5
35.5
13.5
13.4
35.1
32.7
0.22
0.59
4.05
122
3.20
3.28
165
ns
Gross
Margin*
($/ha)
23
232
23
232
-39
217
160
180
15
224
183
Cumulative
Gross Margin*
($/ha)
368
880
354
962
310
447
377
312
376
852
1145
7
Appendix 1. Waikerie Trial Plan 2005
2005 SA Core Trial (4 replications per treatment) All Treatments Sown 20/6/05
Treat
No
1
Rotation
Pasture/ Wheat
Tilla
ge
CC
Fertiliser
Nil
2
Wheat/ Pasture
CC
50 kg/ha MAP
3
Pasture/ Wheat
CC
Nil
4
Wheat/ Pasture
DD
5
W/V/W/Pe/W/V/W/W
6
V/W/Pe/W/Tr/VW/W
DD/
CC
CC
7
V/W/Pe/W/C/C/W/W
DD
8
9
10
11
W/V/W/Pe/W/V/W/W
Canola/ Wheat
DD
DD
50 kg/ha MAP
Variety/Sowin
g Rate
Self sown
Wheat Seed @
70kg/ha
Self sown
Wheat Seed @
70kg/ha
2002
2003
2004
Yitpi
Pasture
Self-sown
Yitpi
Pasture
Self sown
Pasture
Wheat
Yitpi
Regen
pasture
Wheat
Yitpi
Yitpi
Pasture
Self Sown
Yitpi
Pasture
Wheat
Yitpi
Regen
Pasture
Yitpi
Vetch
Yitpi
Triticale
Vetch
Yitpi
Canola
Canola
ATR Eyre
Yitpi
2005
100kg/ha
75kg/ha MAP+2%Zn,
30kg/ha Urea
75kg/ha MAP, 2%Zinc,
30kg/ha Urea
Wheat seed @
70 kg/ha
Wheat seed @
70 kg/ha
75kg/ha MAP+2%Zn
30kg/ha Urea
Wheat seed @
70 kg/ha
Yitpi
Vetch
Yitpi
Yitpi
Wheat
150 kg/ha super P, 70kg/ha
Urea
Canola @
5kg/ha
Yitpi
Canola
ATR Eyre
Yitpi
Eyre
Canola
Krichauff
Clearfld
Janz
Clearfld
Stiletto
Cf Stiletto
Krichauff
Krichauff
Yitpi
Cf Stiletto
DD/
CC
75kg/ha MAP, 2%Zinc,
30kg/ha Urea
Clearfield @
70kg/ha
W/W/C/W/W/W/W/Cf
W
RT
75kg/ha MAP, 2%Zinc,
30kg/ha Urea or
Clearfield @
70kg/ha
District Practice.
District Practice.
High Input.
Pasture
Self sown
Wheat
Yitpi
75kg/ha MAP+2% Zinc
Vet/W/W/W/W/CfW/Cf
W/CfW
Comments
Kaspa Peas
Yitpi
Wheat
Yitpi
Wheat
District Practice.
Changed to CC Dec 04
Changed to high cultivation CC
(Gupta expt) 03
High Input Pulse/Cereal rotation
till 2004
High Input. Canola/Wheat rotation
Atrazine applied post sowing
Clearfield herbicide in 2003-04
Clearfield sown 2005 but
conventional herbicides used
High Input
Opportunity Cropping poor in
2004, grassy: 2005 Clearfield
wheat for grass control, Midas
herbicide applied
9
Appendix 2.
Waikerie Water 2005
Sowing Volumetric Moisture (mm) (15/6/05)
DP CC DP CC
Past/Wh Wh/Past
Treatment
1
2
0-10
5.70
5.43
10-20
7.42
7.28
20-40
13.14
18.25
40-60
9.64
17.14
60-80
15.33
18.52
80-100
22.02
29.99
Total 1M
73.2
96.6
Ad CC
Wh/Wh
5
5.06
6.90
15.78
13.52
19.88
30.45
Ad CC
Wh/Wh
6
4.97
6.13
14.44
15.51
19.71
27.49
Ad DD
Wh/Wh
8
5.08
6.70
15.40
16.36
19.92
34.27
Ad CC
Wh/Wh
10
4.98
7.08
17.48
17.24
20.78
34.60
Ad RT
Wh/Wh
11
5.3
6.6
15.8
16.9
20.2
29.6
91.6
88.2
97.7
102.2
94.4
Harvest Volumetric Moisture (mm) (17/11/05)
DP CC
Wh/Past
Treatment
2
0-10
2.17
10-20
5.62
20-40
10.90
40-60
9.63
60-80
18.93
80-100
32.97
Total 1M
80.2
Ad CC
Wh/Wh
6
2.33
4.27
9.39
12.08
18.76
28.82
Ad DD
Wh/Wh
8
2.02
4.54
8.78
12.22
23.35
36.31
Ad RT
Wh/Wh
11
2.2
5.2
9.5
10.1
20.5
35.6
75.6
87.2
83.1
Water Used: mm of water used (sowing – harvest)
DP CC Ad CC
Wh/Past Wh/Wh
Treatment
2
6
3.26
2.64
0-10
1.65
1.86
10-20
7.36
5.05
20-40
7.52
3.43
40-60
-0.41
0.95
60-80
-2.98
-1.32
80-100
Total 1M
16.4
12.6
Ad DD
Wh/Wh
8
3.05
2.15
6.62
4.14
-3.43
-2.05
Ad DD
Wh/Wh
11
3.12
1.47
6.21
6.84
-0.33
-6.05
10.5
11.3
10
Appendix 3.
Waikerie Nitrogen 2005
Sowing Mineral Nitrogen (kg/ha) (15/6/05)
DP CC
Past/Wh
Treatment
1
0-10
10.04
10-20
10.84
20-40
19.07
40-60
13.32
60-80
18.83
80-100
21.57
Total 1M
93.7
DP CC
Wh/Past
2
25.87
10.26
16.32
13.55
12.28
17.94
Ad CC
Wh/Wh
5
9.99
11.23
18.41
18.28
35.53
46.32
Ad CC
Wh/Wh
6
12.22
13.73
16.50
19.78
26.40
27.51
Ad DD
Wh/Wh
8
13.64
12.07
20.95
25.35
31.22
48.54
Ad CC
Wh/Wh
10
14.79
7.68
11.84
14.33
10.84
25.93
Ad RT
Wh/Wh
11
6.99
11.53
14.50
10.54
12.36
16.34
96.2
139.8
116.2
151.8
85.4
72.3
Harvest Mineral Nitrogen (kg/ha) (17/11/05)
DP CC
Wh/Past
Treatment
2
0-10
4.06
10-20
1.48
20-40
1.47
40-60
2.09
60-80
7.40
80-100
19.80
Total 1M
36.3
Ad CC
Wh/Wh
6
4.20
1.85
1.81
2.12
5.35
32.16
Ad DD
Wh/Wh
8
6.04
2.06
2.60
2.50
36.75
34.22
Ad RT
Wh/Wh
11
3.64
1.54
1.53
0.90
9.67
26.45
47.5
84.2
43.7
Nitrogen Used: Kg/ha of N used (sowing – harvest)
DP CC
Wh/Past
2
Treatment
21.82
0-10
8.78
10-20
14.85
20-40
11.47
40-60
4.88
60-80
-1.86
80-100
Total 1M
59.9
Ad CC
Wh/Wh
6
8.02
11.88
14.69
17.66
21.06
-4.65
Ad DD
Wh/Wh
8
7.60
10.01
18.35
22.85
-5.52
14.32
68.7
67.6
Ad DD
Wh/Wh
11
3.35
9.99
12.97
9.63
2.69
-10.12
28.5
11
Appendix 4. Additional Demonstration/Observation Trials
Wheat variety dry sowing demonstration trial
Aim: to investigate the performance of conventional and Clearfield wheat varieties when
dry sown and sown after the seasons break.
Varieties
• Clearfield Janz
• Clearfield Stiletto
• Yitpi
• Wyalcatchem
Each variety was sown dry on the 2nd of June then again after the break on the 20th of June
with 3 replicates per treatment. Sowing rate (70 kg/ha) and fertiliser (75 kg/ha MAP +
2%Zn and 30 kg/ha Urea) was the same for all varieties. The break to the season occurred
on the 9th of June.
Results
Variety
Sowing
Clearfield Janz
Clearfield Janz
Clearfield Stiletto
Clearfield Stiletto
Yitpi
Yitpi
Wyalcatchem
Wyalcatchem
Dry sow
After Break
Dry sow
After Break
Dry sow
After Break
Dry sow
After Break
1.60
1.73
1.81
1.77
1.65
2.20
1.68
1.87
LSD P=0.05
0.28
Yield t/ha
The dry sown treatments all looked more advanced and vigorous early as expected
however good rains through spring allowed the later sown treatments to catch up. The only
variety to show a significant difference between dry and later sowing was Yitpi where the
later sowing yielded higher, possibly as a result of higher weed burden in the early sown
treatment. Weed control took place at the same time regardless of sowing date and had the
dry sown treatments been sprayed earlier (which may have been possible) then they may
have maintained an advantage particularly in the Clearfield varieties where grass weeds
would have been controlled earlier.
12
Observation Trials
1. Aim: to investigate the value of additional fertiliser Nitrate given expected adequate soil
N to meet potential yield.
Results
Treatment
Clearfield Stiletto with MAP+ Zn @ 75 kg/ha
Clearfield Stiletto with MAP+ Zn @ 75 kg/ha + Urea @ 30 kg/ha
Yield t/ha Protein %
1.86
1.99
13.6
14.2
Although the addition of extra fertiliser N gave a slightly higher yield and protein this was
not statistically significant.
2. Aim: to investigate the performance of two wheat varieties sown alone and in a blend
(some evidence exists for higher yields when different varieties are sown together).
Results
Treatment
Yitpi Wheat
Yield t/ha
Wyalcatchem Wheat
2.43
1.92
Yitpi and Wyalcatchem Blend 50:50
2.31
Sown alone Yitpi out yielded Wyalcatchem while in a blend the yield was in between,
which provides no evidence of a synergistic effect with these varieties.