jenkinson, rebecca - stubble management for the incidence and … powerpoints/jenkinson, rebecca -...
TRANSCRIPT
Role of stubble management on the severity and duration of frostRebecca JenkinsonFebruary 2014
Outline• How stubble increases the severity and duration
of frost• The position in the landscape on frost severity• Yield and quality impacts
2012 Research• Standing stubble:• Treatments were 1°C colder
• Total time below 0 degrees is longer (9 hours vs 8 hours)
• Lower yield (0.39t/ha vs 1.71t/ha)
2012 Research• PA trials in York
2013 AimsTo quantify the impact of stubble on the extent, severity and duration of frost and determine its effect on canopy temperature and grain yield.
– Retaining stubble increases frost severity– Retaining stubble increases duration of frost
Decreased yield=
Method• Large scale replicated trials• Three locations: Nyabing, Wickepin & York• Two main treatments
– Standing and removed stubble
• Placement of tiny tags along the slope
York & Wickepin
Results: York
-2.5
-2.0
-1.5
-1.0
-0.5
0.0
0.5
1.0
16th Aug 20th Aug 23rd Aug 24th Aug 6th Sep 27th Sep 28th Sep 1st Oct 10th Oct 13th Oct 14th Oct 15th Oct Ave
Frost Severity
Standing
Removed
Flowering window
12 – 22 Sept
a
a
aa
a
a
a
a
a
a
a
a
a
b
b
b
b
b
b
b
b
b
b
b
b
b
LSD=0.16
Tem
pe
ratu
re °C
AVERAGE
Standing: -1.1°C
Removed: -0.6°C
Results: WickepinAVERAGE
Standing: -0.7°C
Removed: -0.5°C
Cultivated: 0.2°C
-2.0
-1.5
-1.0
-0.5
0.0
0.5
1.0
1.5
14th Aug 16th Aug 6th Sept 27th Sept 1st Oct 10th Oct 12th Oct 13th Oct 22nd Oct AVE
Frost Severity
Standing
Removed
Cultivated
a
a
a
a
c
c
c
a
a
aa
aa
aa
a
ab
a
aa
bb
b
b
b
b
bb
b
b
LSD=0.32
Flowering window
18 – 24 Sept
Tem
pe
ratu
re °C
NyabingRemoved
RemovedRemovedStanding
StandingStanding
Additional
stubble
Photo: Steve
Curtin
48m
300m
Nyabing
Photos: Fiona Martin
Raked Stubble Plot (0.5t/ha) Additional Stubble Plot (3.5t/ha)
Results: Nyabing
-5
-4
-3
-2
-1
0
5th Sept 6th 9th 27th 28th 1st Oct 10th 12th 13th 14th 15th 17th 18th 21st 22nd AVG
Frost Severity
Additional
Stubble
Removed
b
b
b
bb
b
b b
b
c
c
c
c
c
c
c
a
a
a
a
a
aa
a
aa
a
a
aa
a
a
a
b
b
bb
bb
bb
bb
LSD = 0.17
a
bc
Flowering window
Tem
pe
ratu
re °C
Grain fill
AVERAGE
Additional: -2.4°C
Standing: -2°C
Removed: -1.8°C
Frost and cold susceptible stages
Results: Nyabing
-5
-4
-3
-2
-1
0
5th Sept 6th 9th 27th 28th 1st Oct 10th 12th 13th 14th 15th 17th 18th 21st 22nd AVG
Frost Severity
Additional
Stubble
Removed
b
b
b
bb
b
b b
b
c
c
c
c
c
c
c
a
a
a
a
a
aa
a
aa
a
a
aa
a
a
a
b
b
bb
bb
bb
bb
LSD = 0.17
a
bc
Flowering window
Tem
pe
ratu
re °C
Grain fill
AVERAGE
Additional: -2.4°C
Standing: -2°C
Removed: -1.8°C
Results: Nyabing
a
a
a
a
a
b
b
b
a
a
a
b
b
a
a
0
10
20
30
40
50
60
70
0°C -1°C -2°C -3°C -4°C
Cu
mu
lati
ve
ho
urs
be
low
0
Duration below temperature thresholds
Additional
Standing
Removed
Results: Nyabing
a
a
a
a
a
b
b
b
a
a
a
b
b
a
a
0
10
20
30
40
50
60
70
0°C -1°C -2°C -3°C -4°C
Cu
mu
lati
ve
ho
urs
be
low
0
Duration below temperature thresholds
Additional
Standing
Removed
Photo: Steve Curtin, Nov 2013
306m above sea level
303m above sea level
Results: Nyabing Yield
Yield LSD0.05
HI LSD0.05
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.0
0.5
1.0
1.5
2.0
2.5
3.0
Additional Standing Removed Standing Removed
Low landscape High landscape
Ha
rve
st I
nd
ex
Gra
in Y
ield
(t/
ha
)
Yield (t/ha) Harvest Index
0
10
20
30
40
50
60
70
80
90
100
Additional Standing Removed Standing Removed
Low landscape High landscape
Fro
st I
nd
uce
d S
terl
ity
(%
)
FIS LSD0.05
Results: Nyabing Yield
Results: Nyabing
Screenings: 56%
Frosted grain: 34%Screenings: 9%
Frosted grain: 14%
Screenings: 9%
Frosted grain: 16%
Additional Stubble Standing Removed
Screenings LSD = 5.5
Frosted Grain LSD = 17.7
Summary of 2013 Project• 3 sites; Nyabing, Wickepin and York• Standing and removed stubble treatments• Canopy temperature & yield components• Assessing the severity and duration of frost
Key messages• Stubble increased severity and duration of frost• Removing stubble reduced frost damage • Reducing stubble in high frost prone
environments = higher yield– 0.6t/ha vs 1.8t/ha
NSW Research2013 wheat yield (t/ha) 2013 canola yield (t/ha) 2012 wheat yield (t/ha)
Treatment
Burn
(30% frost
damage)
Retain
(59% frost
damage)
Burn
(43% frost
damage)
Retain
(59% frost
damage)
Burn
(10% frost
damage)
Retain
(10% frost
damage)
Nil graze 3.3 2.2 1.0 0.7 5.0 4.4
Stubble graze 3.6 3.0 1.1 0.9 4.8 4.8
P value <0.001 0.014 0.003
LSD (P<0.05) 0.2 0.1 0.3
Information courtesy James Hunt CSIRO & Farmlink
Results: Nyabing
Position Low landscape High landscape
Stubble Additional Standing Removed Standing Removed LSD0.05
Yield (t/ha) 1.9 2.5 0.40
Yield (t/ha) –map 0.6 1.0 1.8 0.30
FIS (%) 87 33 35 20 13 4.0
HI 0.02 0.26 0.24 0.28 0.32 0.10
100GW (mg) 16 46 45 43 44 3.0
Screenings (%) <2mm 56 9 9 13 13 5.5
Frosted grain (%) 34 14 16 17.7
Results: Wickepin
PositionLow landscape Mid landscape High landscape
StubbleStanding Removed Cultivated Standing Removed Cultivated Standing Removed Cultivated
LSD0.05
Yield (t/ha) 4.4 4.4 4.61 5.0 3.9 5.09 3.0 3.6 4.51 0.941
FIS (%) 11 10 10 9 9 10 12 8 6 1.9
HI 0.38 0.36 0.39 0.36 0.33 0.36 0.30 0.29 0.38 0.043
100GW (mg) 39 38 37 39 41 41 38 41 44 NS
Screenings (%)
<2mm 15 19 21 14 11 15 23 11 6 NS
Frosted grain (%) 0.5 0.2 0.3 0.3 0.3 0.6 0.5 0.5 0.3 NS
Results: York
PositionLow landscape Mid landscape High landscape
StubbleStanding Removed Standing Removed Standing Removed
LSD0.05
Yield (t/ha) 4.5 3.4 4.8 5.1 5.0 4.8 0.75
FIS (%) 4 3 5 4 4 4 1.0
HI 0.36 0.35 0.37 0.39 0.38 0.38 0.015
100GW (mg) 33 32 35 35 35 34 2.4
Screenings (%) <2mm 50 50 36 35 35 40 10.3
Frosted grain (%) 1.0 0.6 0.3 0.2 0.2 0.3 0.46
Frost Induced Sterility (FIS) estimation
On this side of the head
• 10 pairs of spikelets,= 20 florets in total,
• 9 florets frosted
• 11 florets viable
• Count the other side of the head as well
If we assume it’s the same ratio then calculate damage as;
FIS = 18/40x100 = 45%
Discard
Discard
12
345
678
10 frosted
frosted
frosted
frostedfrosted
frostedfrosted
frosted
frosted
viable
viable
viable
viableviable
viable
viableviableviableviable
viable