ارزیابی واندازه گیری محصول (غلات)2
Table used to estimate the amount of water in your soil by feel
Red values are the amount of water potentially available to roots per metre of soil depth
Sand,
loam sand
Sand loam,
silt loam
Loam,
clay loam
Light clay,
clay
Above
Field Capacity
water appears if
soil is bounced
in your hand
water released
when soil is
kneaded
you can squeeze
water out of the
soil
undisturbed soil
has a water
sheen
At
Field Capacity
no free water appears on the soil when it is squeezed
but a wet outline of the soil ball remains on the hand
water available
60-100 mm
100-150 mm
150-200 mm
200-250 mm
75-100% of
Field Capacity
sticks together
slightly, may just
form a ball
forms a ball
but it breaks
easily
forms a ball
that is very
pliable
ribbons flat
between the
fingers
water available
±70 mm
±110 mm
±155 mm
±200 mm
50-75% of
Field Capacity
(stress likely)
seems dry and
will not form a
ball when
squeezed
forms a ball
which does
not hold
together
forms a ball,
which is
somewhat
plastic
forms a ball
and ribbons
between fingers
water available
±50 mm
±80 mm
±110 mm
±140 mm
Determining rooting depth and any barrier to root penetration
This method follows Lafitte (1994). The root system of a mature wheat plant can reach a depth of 1 to 1.2 m, but if some barrier exists in the soil above 1.2 m, the roots will stop at the barrier and be unable to tap deeper water and nutrients. Potential yields will be reduced. If there seems to be a problem check for barriers in two or three places in a field though one place may be adequate if the crop looks uniform and is on a level area.
Pick an area where the plants look uniform, and start digging with a spade, preferably when the soil is near field capacity (p 16), as digging in dry soil can be difficult. Dig until you strike any barrier. This can be a plough pan, a hard pan, a rock layer, an impermeable clay layer, acid subsoil, a water table, or a salt band. If you are uncertain that what you find is a barrier, examine the roots of the crop to see if they penetrate the area. If not, record this depth. Dig to about 40 cm, as plough pans usually form above this level and use a soil corer from there to 1m. Break the cores at several places to see if roots are still present at different depths.
Field sheets. A guide to recording your observations
You will find the field sheets in a pocket at the end of this booklet. There are two sets of pages; the first includes example data from an actual crop and pictures of the Zadoks growth stages while the second set is blank for you to add your own data. Make as many copies as you need and then replace the originals for future use. In case someone borrows the originals, A5 (small) copies are included here.
Take a copy of the field sheets with you to the field to help determine growth stages of the crop and so you can write down your observations and counts in a structured way. Use the same field sheet each time you visit that field. At each visit, make notes of unusual conditions of the crop such as herbicide damage, frosted leaf tips, frost damage on spikes and any leaf curling. An accurate record of crop management as the season progresses (sowing, fertilizers, weed and disease control, irrigations, harvest) will help you to identify which factors limit yield most.
At each visit, write down the date in the first column opposite the plant growth stage that you have identified. Notes in the second column and pictures on the sample sheets will help you to decide on the plant growth stage. The third column is for your estimate of ground cover (p 14) as it increases from seedling emergence towards flowering (p 44) and green leaf number reductions thereafter (p 14 and p 48). Pages 44 and 48 tell you what numbers to expect. The fourth column is for a summary of your management decisions as the crop advances and for dates of your actions. The rows that cut across the full table width are for your calculations of the state of the crop. Example target numbers for a high yielding crop are provided for comparison. If your calculated numbers disagree substantially with the targets, things that you might like to check in your crop are also listed in those rows.
farmer name: Ngyuen
field: NW Paddock variety: Kanchan
Field Sheet 1
date
GROWTH STAGES
MANAGEMENT DECISIONS & ACTIONS
CODE
DESCRIPTION
MANAGEMENT BEFORE THE CROP EMERGES
When growth stage seen
pre-sowing fertilizer:
pre-emergence herbicides:
type:............................
type:...............................
date /rate /.....................
date / rate /........................
crop on: /beds /flat/
row spacing:... 18 cm.........
1/5
0.0
Sowing
seed size: small / medium / large
seed treatment Vitavax 200..
sowing depth (cm):/ 0 / 2 / 4 / 6 / 8 /
sowing rate (kg/ha): 100 kg/ha
0.3
germination, seed swollen
sowing fertilizer:
seedbed: / very dry / dry / moist / wet
0.5
radicle emerged from seed
type:.. S tarter 12.....
tilth: / poor / good / excellent /
07
coleoptile emerged
date / rate / 1 May / 120 kg/ha.
watered up: / yes / no /
8/5
1.0
Emergence
crust after sawing: none / moderate / bad
your individual seedling counts: 29 31 35 32 40 38 22 29 30 27 40 38 41 32 33 39 38 44 42 35 41 46 38 38 43 45 /m row
(A)
av. seedling establishment
37
target 30 - 40 plants/m row length if using 18 cm row spacing
POOR STAND?
CHECK THESE
crust/ water stress / low seeding rate / sowing too deep / bad seed / bad seedbed / weeds / waterlogging /
bad incorporation of residues / nutrient problem / herbicide toxicity / birds / insects / diseases
Leaves on main shoot
Ground cover
MANAGEMENT AFTER THE CROP EMERGES
1.1
1st leaf more than half visible
fertilizer/type/: urea...
23/5
1.2
2nd leaf more than half visible
20%
date / rate / 19/6 90 kgN/ha
11/6
1.3
3rd leaf more than half visible
30%
1.4
4th leaf more than half visible
fertilizer/type/ urea......
3/7
1.5
5th leaf more than half visible
50%
date / rate / 14 /9 25 kgN /ha.
25/7
1.6
6th leaf more than half visible
80%
12/8
1.7
7th leaf more than half visible
95%
fertilizer/type/:..................
1.8
8 or more leaves visible and stem not elongating
date /rate /......................
aim for 120 shoots/ m row length
the target number of tillers/plant is therefore (120 / (A) ) -1 = 2.2 tillers
example for 30 plants / m row length the target is 3 or more tillers per main shoot if using 18 cm row spacing
Tillering
11/6
2.1
main shoot and 1 tiller
herbicide/type/:................
weeds:....................................
2.2
main shoot and 2 tillers
date /rate /.....................
results: / poor / good / excellent /
3/7
2.3
main shoot and 3 tillers
25/7
2.4
main shoot and 4 tillers
herbicide/type/:................
weeds:...................................
12/8
2.5
main shoot and 5 tillers
date / rate /.....................
results: / poor / good / excellent /
2.6
main shoot and 6 tillers
2.7
main shoot and 7 tillers
16/8
Stem elongation
3.1
1st node detectable
fungicide/type/: T, H..........
disease:... stripe rust......
5/9
3.2
2nd node detectable
100%
date / rate /... 12/9 250m l/ha.
% infected:... 5%.................
3.3
3rd node detectable
3.4
4th node detectable
fungicide/type/:T, H..........
disease:... stripe rust...
3.5
5th node detectable
date / rate /... 9/10 250m l/ha.
% infected:... 5%................
ground cover at this stage should be more than 90% (= effectively complete)
the N° of shoots with nodes is a first approximation of final spike number. Target is at least 85 of these shoots /m row
IF POOR GROUND COVER, OR
sowing too deep / frost / water stress / nutrient problem /
IF LOW SHOOT NUMBER CHECK THESE
diseases / insects / waterlogging / weeds
CROP UNHEALTHY? CHECK THESE
nutrients/ diseases / water stress / insects / frost / lodging / waterlogging / salinity
farmer:
field: NW Paddock
variety: Kanchan
Field Sheet 2
date
GROWTH STAGES
MANAGEMENT DECISIONS / ACTIONS
CODE
DESCRIPTION
Ground
Irrigations
Booting stages
cover
1. dates 27/9......
to... 28/9...
3.7
Hag leaf visible
volume....................
13/9
3.9
lag leaf collar just visible
100%
wilting score... 1........
4.1
early boot, flag leaf sheath extending
4.3
mid boot, boot opposite collar of 2nd last leaf
2. dates 26/10......
to... 27/10.........
4.5
late boot, boot above collar of 2nd last leaf
volume......................
23/9
4.7
tag leaf sheath opening
wilting score... 0.........
4.9
first awns visible
Heading stages
3. dates... 13/11......
to... 14/11...
5.0
1st spikelet of spike just visible
volume......................
5.2
20% of spike visible, early heading
wilting score... 0......
5.5
50% of spike visible, mid heading
5.8
80% of spike visible, late heading
4/10
6.0
full heading, but not flowering
your individual spike counts: 83 106 127 115 96 105 120 115 118 125 /m row length
(B)
your average spike number...... 111... target 80 - 100 spikes /m row length (18 cm row width)
IF LOW SPIKE NUMBER CHECK THESE
frost / insects / water stress / nutrient problem / diseases
Red values are the amount of water potentially available to roots per metre of soil depth
Sand,
loam sand
Sand loam,
silt loam
Loam,
clay loam
Light clay,
clay
Above
Field Capacity
water appears if
soil is bounced
in your hand
water released
when soil is
kneaded
you can squeeze
water out of the
soil
undisturbed soil
has a water
sheen
At
Field Capacity
no free water appears on the soil when it is squeezed
but a wet outline of the soil ball remains on the hand
water available
60-100 mm
100-150 mm
150-200 mm
200-250 mm
75-100% of
Field Capacity
sticks together
slightly, may just
form a ball
forms a ball
but it breaks
easily
forms a ball
that is very
pliable
ribbons flat
between the
fingers
water available
±70 mm
±110 mm
±155 mm
±200 mm
50-75% of
Field Capacity
(stress likely)
seems dry and
will not form a
ball when
squeezed
forms a ball
which does
not hold
together
forms a ball,
which is
somewhat
plastic
forms a ball
and ribbons
between fingers
water available
±50 mm
±80 mm
±110 mm
±140 mm
Determining rooting depth and any barrier to root penetration
This method follows Lafitte (1994). The root system of a mature wheat plant can reach a depth of 1 to 1.2 m, but if some barrier exists in the soil above 1.2 m, the roots will stop at the barrier and be unable to tap deeper water and nutrients. Potential yields will be reduced. If there seems to be a problem check for barriers in two or three places in a field though one place may be adequate if the crop looks uniform and is on a level area.
Pick an area where the plants look uniform, and start digging with a spade, preferably when the soil is near field capacity (p 16), as digging in dry soil can be difficult. Dig until you strike any barrier. This can be a plough pan, a hard pan, a rock layer, an impermeable clay layer, acid subsoil, a water table, or a salt band. If you are uncertain that what you find is a barrier, examine the roots of the crop to see if they penetrate the area. If not, record this depth. Dig to about 40 cm, as plough pans usually form above this level and use a soil corer from there to 1m. Break the cores at several places to see if roots are still present at different depths.
Field sheets. A guide to recording your observations
You will find the field sheets in a pocket at the end of this booklet. There are two sets of pages; the first includes example data from an actual crop and pictures of the Zadoks growth stages while the second set is blank for you to add your own data. Make as many copies as you need and then replace the originals for future use. In case someone borrows the originals, A5 (small) copies are included here.
Take a copy of the field sheets with you to the field to help determine growth stages of the crop and so you can write down your observations and counts in a structured way. Use the same field sheet each time you visit that field. At each visit, make notes of unusual conditions of the crop such as herbicide damage, frosted leaf tips, frost damage on spikes and any leaf curling. An accurate record of crop management as the season progresses (sowing, fertilizers, weed and disease control, irrigations, harvest) will help you to identify which factors limit yield most.
At each visit, write down the date in the first column opposite the plant growth stage that you have identified. Notes in the second column and pictures on the sample sheets will help you to decide on the plant growth stage. The third column is for your estimate of ground cover (p 14) as it increases from seedling emergence towards flowering (p 44) and green leaf number reductions thereafter (p 14 and p 48). Pages 44 and 48 tell you what numbers to expect. The fourth column is for a summary of your management decisions as the crop advances and for dates of your actions. The rows that cut across the full table width are for your calculations of the state of the crop. Example target numbers for a high yielding crop are provided for comparison. If your calculated numbers disagree substantially with the targets, things that you might like to check in your crop are also listed in those rows.
farmer name: Ngyuen
field: NW Paddock variety: Kanchan
Field Sheet 1
date
GROWTH STAGES
MANAGEMENT DECISIONS & ACTIONS
CODE
DESCRIPTION
MANAGEMENT BEFORE THE CROP EMERGES
When growth stage seen
pre-sowing fertilizer:
pre-emergence herbicides:
type:............................
type:...............................
date /rate /.....................
date / rate /........................
crop on: /beds /flat/
row spacing:... 18 cm.........
1/5
0.0
Sowing
seed size: small / medium / large
seed treatment Vitavax 200..
sowing depth (cm):/ 0 / 2 / 4 / 6 / 8 /
sowing rate (kg/ha): 100 kg/ha
0.3
germination, seed swollen
sowing fertilizer:
seedbed: / very dry / dry / moist / wet
0.5
radicle emerged from seed
type:.. S tarter 12.....
tilth: / poor / good / excellent /
07
coleoptile emerged
date / rate / 1 May / 120 kg/ha.
watered up: / yes / no /
8/5
1.0
Emergence
crust after sawing: none / moderate / bad
your individual seedling counts: 29 31 35 32 40 38 22 29 30 27 40 38 41 32 33 39 38 44 42 35 41 46 38 38 43 45 /m row
(A)
av. seedling establishment
37
target 30 - 40 plants/m row length if using 18 cm row spacing
POOR STAND?
CHECK THESE
crust/ water stress / low seeding rate / sowing too deep / bad seed / bad seedbed / weeds / waterlogging /
bad incorporation of residues / nutrient problem / herbicide toxicity / birds / insects / diseases
Leaves on main shoot
Ground cover
MANAGEMENT AFTER THE CROP EMERGES
1.1
1st leaf more than half visible
fertilizer/type/: urea...
23/5
1.2
2nd leaf more than half visible
20%
date / rate / 19/6 90 kgN/ha
11/6
1.3
3rd leaf more than half visible
30%
1.4
4th leaf more than half visible
fertilizer/type/ urea......
3/7
1.5
5th leaf more than half visible
50%
date / rate / 14 /9 25 kgN /ha.
25/7
1.6
6th leaf more than half visible
80%
12/8
1.7
7th leaf more than half visible
95%
fertilizer/type/:..................
1.8
8 or more leaves visible and stem not elongating
date /rate /......................
aim for 120 shoots/ m row length
the target number of tillers/plant is therefore (120 / (A) ) -1 = 2.2 tillers
example for 30 plants / m row length the target is 3 or more tillers per main shoot if using 18 cm row spacing
Tillering
11/6
2.1
main shoot and 1 tiller
herbicide/type/:................
weeds:....................................
2.2
main shoot and 2 tillers
date /rate /.....................
results: / poor / good / excellent /
3/7
2.3
main shoot and 3 tillers
25/7
2.4
main shoot and 4 tillers
herbicide/type/:................
weeds:...................................
12/8
2.5
main shoot and 5 tillers
date / rate /.....................
results: / poor / good / excellent /
2.6
main shoot and 6 tillers
2.7
main shoot and 7 tillers
16/8
Stem elongation
3.1
1st node detectable
fungicide/type/: T, H..........
disease:... stripe rust......
5/9
3.2
2nd node detectable
100%
date / rate /... 12/9 250m l/ha.
% infected:... 5%.................
3.3
3rd node detectable
3.4
4th node detectable
fungicide/type/:T, H..........
disease:... stripe rust...
3.5
5th node detectable
date / rate /... 9/10 250m l/ha.
% infected:... 5%................
ground cover at this stage should be more than 90% (= effectively complete)
the N° of shoots with nodes is a first approximation of final spike number. Target is at least 85 of these shoots /m row
IF POOR GROUND COVER, OR
sowing too deep / frost / water stress / nutrient problem /
IF LOW SHOOT NUMBER CHECK THESE
diseases / insects / waterlogging / weeds
CROP UNHEALTHY? CHECK THESE
nutrients/ diseases / water stress / insects / frost / lodging / waterlogging / salinity
farmer:
field: NW Paddock
variety: Kanchan
Field Sheet 2
date
GROWTH STAGES
MANAGEMENT DECISIONS / ACTIONS
CODE
DESCRIPTION
Ground
Irrigations
Booting stages
cover
1. dates 27/9......
to... 28/9...
3.7
Hag leaf visible
volume....................
13/9
3.9
lag leaf collar just visible
100%
wilting score... 1........
4.1
early boot, flag leaf sheath extending
4.3
mid boot, boot opposite collar of 2nd last leaf
2. dates 26/10......
to... 27/10.........
4.5
late boot, boot above collar of 2nd last leaf
volume......................
23/9
4.7
tag leaf sheath opening
wilting score... 0.........
4.9
first awns visible
Heading stages
3. dates... 13/11......
to... 14/11...
5.0
1st spikelet of spike just visible
volume......................
5.2
20% of spike visible, early heading
wilting score... 0......
5.5
50% of spike visible, mid heading
5.8
80% of spike visible, late heading
4/10
6.0
full heading, but not flowering
your individual spike counts: 83 106 127 115 96 105 120 115 118 125 /m row length
(B)
your average spike number...... 111... target 80 - 100 spikes /m row length (18 cm row width)
IF LOW SPIKE NUMBER CHECK THESE
frost / insects / water stress / nutrient problem / diseases
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