RAPID ACCESS TO THE LATEST REGIONAL CROP PEST AND DISEASE LEVELS
Regional Crop Report South West , 13 April 2007
Winter Wheat
Comment on current growth stages
Field conditions
Early sown crops now at GS 32 with leaf 3 at 10 % emerged on September
sowings of Alchemy and early October Einstein.
The
top few millimetres of most soils are very dry however below this
layer moisture is still more than adequate. Until a fuller canopy
develops and starts extracting water vigorously soil below this layer
will not dry much more. Think how damp setaside pulls up even after
a dry summer. Wheat crops, with roots below this layer, are not currently
suffering from moisture stress. Advantage has
been taken of the dry period to roll some very puffy seedbeds. Wheat
has responded well to this as root soil contact has been greatly improved.
Main
diseases Present
Level
and comment
Brown
Rust
None
seen
Mildew
Levels
still very low even on very susceptible varieties.
Septoria
tritici
Older
overwintered leaves heavily infected on most varieties. No infection
seen on leaf 4 or 5.
Yellow
Rust
No
further outbreaks.
Eyespot
Lesions
have not penetrated much further into stem walls.
Other
None
seen.
Main
Pest problems
Level
and comment
Aphids
Untreated
crops in need of treatment.
Frit
fly
None
seen
Leatherjacket
No
reports of further damage.
Opomyza
None
seen
Slugs
No
reports of further damage.
Wheat
bulb fly
None
seen
Wireworm
None
seen
Other
None
seen
Main
weed problems
Level
and comment
Blackgrass
Any
untreated area will be left until days lengthen in Late Feb./early
March.
Meadow
grasses
Well
controlled by pre emergence materials.
Rye
grass
Pre ems have worked well,
follow up treatments now being applied.
Rapid growth has occurred and as usual in early April barley has overtaken
wheat in the growth stage stakes. T1 fungicides have been applied
to most crops.
The
top few millimetres of most soils are very dry however below this
layer moisture is still more than adequate. Until a fuller canopy
develops and starts extracting water vigorously soil below this layer
will not dry much more. Think how damp setaside pulls up even after
a dry summer. Crops, with roots below this layer, are not currently
suffering from moisture stress. Advantage has
been taken of the dry period to roll some very puffy seedbeds. Crops
have responded well to this as root soil contact has been greatly improved.
Main
diseases Present
Level
and comment
Brown
Rust
Low
levels at stem base
Mildew
At
low levels in most varieties.
Net-blotch
No
change.
Yellow
Rust
None
seen
Eyespot
None
seen
Rhynchosporium
Has
not progressed significantly in the dry conditions.
Other
Some
of the most forward crops are now showing severe abiotic spotting
often linked with manganese deficiency.
Remarkable
growth in the last week with a significant number of crops at 50%
pods set on main raceme. Very few blind pod sites at this stage suggesting
minimal pollen beetle damage. Light Leaf Spot: low levels have been
seen although previously applied PGR triazoles should take care of
this.
Main
diseases Present
Level
and comment
Club
root
No
fresh reports.
Downy
Mildew
None
seen
Light
Leaf Spot
None
seen
Phoma
None
seen
Powdery
Mildew
None
seen
White
Leaf Spot
None
seen
Other
None
seen
Main
Pest problems
Level
and comment
Aphids
None
seen
Flea
beetle
None
seen
Leatherjacket
None
seen
Slugs
None
seen
Other
Seed
weevil can be found at around 1 weevil per 2 plants in some crops.
This is at the threshold for Northern Britain. Threshold in the south
is 1 per plant. Mealy cabbage aphid levels are very high for
so early in the season.
All risk predictions published by CropMonitor are provided in good faith and are NOT a substitute for
rigorous fieldwalking in combination with advice from BASIS qualified persons. CropMonitor accepts no liability
for crop loss or damage resulting from the use of CropMonitor.
