Farming News - Phoma starts to make a mark

Phoma starts to make a mark

 

16 October 2014

A wet week for many has kept machinery out of the fields. Phoma is more easily found this week though nowhere at threshold levels yet. Aphid numbers in oilseed rape are very variable even in the same region, more apparent in the east. Slug activity in winter wheat crops has picked up particularly following oilseed rape.

 

  • Aphids - more reports this week arriving in oilseed rape crops.
  • Slug activity picking up in areas where plenty of rain.
  • Phoma - just beginning to be found in some regions.

 

Winter Wheat

image expired
Gout fly eggs on winter wheat seedlings

South. Once again no significant further drilling since last week due to continuing wet weather. We have now had about 120mm of rain in the last 10 days. Fortunately, around 90% of first wheats were drilled before the weather broke, with the only remaining fields being after potatoes, veg and later maize. Drilling of second wheats is now mostly completed.
Earliest sown wheats now at GS21+ – many fields on heavier soils were showing very uneven emergence due to areas where seedbeds were dry before rain, but for the most part these areas are now filling in. Soils have rapidly become very wet following a further 75mm of rain this week.
Gout fly: gout fly eggs can readily be found. Some fields have 1 or more eggs on every plant.
Slugs: onset of wet weather has dramatically increased surface feeding on fields after oilseed rape in particular. However, in general damage appears to be a lot less widespread than feared, largely due to the quality of seedbeds produced.
Blackgrass: just starting to emerge now in earlier sown crops. Any delayed pre-em applications due to dry seedbeds now being applied as a matter of urgency. Problem fields having Crystal + DFF or Liberator + Defy at pre-/peri-emergence. Fields with difficult blackgrass having Avadex applied ASAP after drilling.


Eastern Counties. Crops range from recently sown through to early tillering. Most second wheat is now in the ground and germinating. 90% of wheat now. Some super seedbeds achieved which is helping establishment. Some sharp showers in the week.
Slugs: no damage yet.
Gout fly: some eggs about but not huge numbers.
Aphids: some seen on early sowings but these crops have had Deter seed dressings. Absent in later sown crops.
Weed control: more Avadex used this year and some robust pre-ems seem to be keeping blackgrass at bay for now.


East Midlands. Forward crops at GS 15-21 but many crops between GS 10 -12 sometimes across the same field. Later drilled crops just chitting. Continued periods of rain with 25-30mm have left soils sticky requiring 2-3 days dry before any more drilling.
Slugs: found in increased numbers and in one case two small fields wiped out by huge numbers requiring re-drilling. Dry weather earlier on has not helped as some crops just chitting and would have grown away if moisture at drilling.
Weed control: pre-ems mainly on and where required Avadex treatments will go on as conditions allow. Second wheats destined to go in awaiting glyphosate pre-drilling but weather is holding sprays up. If wet continues some second wheats may become spring crops.

West Midlands. More localised heavy rain is hampering not only spray operations but also drilling (minimum-tillage has come to an end, back to the plough and combi drill from now). Most forward crops at one to two tiller stage. All early sown wheat crops drilled into dry cloddy seedbeds are now starting to emerge. Most crops have a good colour to them.
Mildew: trace levels on early sown Grafton.
Aphids: easy to find on non Deter dressed crops.
Gout fly: eggs easy to find on forward crops.
Slugs: very few problems have only had to apply Sluxx to very occasional patches of so far.
Weed control: good flush of broad leaf weeds where no pre-ems applied.


North East. Drilling delayed by recent wet weather with rainfall for week: 32 mm. Crops range from still to drill through to 3 leaf stage.
Aphids: T-sum reached for early emerged crops but none seen yet.
Slugs: activity picked up a bit and pellets applied to a few patches.
Weed control: pre-emergence herbicides seem to be working well on blackgrass. Few cleavers now emerging.


Winter Oilseed Rape 

image expired
Phoma starting to enter crops.

South. Crops range from 4 true leaf up to 6-7 leaves – 75% of crops are now around 5-6 true leaves. Crops continue to grow unchecked in response to warm days and nights.
Phoma: first leaf spots beginning to be found this week in a few localities – continuing wet weather will favour spread and infection over the next few weeks and am now anticipating treating most crops when the next weather window permits. Having thought that many crops would escape with a single fungicide this autumn, the change to very unsettled and wet conditions will require a 2-spray approach to combat both Phoma and Light leaf spot.
Light Leaf Spot: none seen to date.
Flea beetle: shot holing of cotyledons/leaves still surprisingly hard to find.
Aphids: low levels of Myzus persicae nymphs beginning to be found in some crops now on up to 10% of plants across the field, but many crops still appear free from any infestation to date. Where >10% plants being found with aphid nymphs on crops are due to be sprayed from next week with either Plenum, Biscaya or Teppeki.
Slugs: after earlier problems, most crops now appear to have grown away from further damage.
Turnip Sawfly: no further larvae being found now following Pyrethroid applications.
Weed control: significant flush of blackgrass in many fields where there is a history of the weed.


Eastern Counties. Rape has continued to grow rapidly in mild moist weather most has now reached 8 – 9 leaves and looking very good indeed. Only poor patches where due to poor seedbeds which were cloddy and dry in September. We have not needed to do any re-drilling, thin patches have filled out and are just part of fields. More rain around 40 mm has continued to help crops. Some areas now lying wet. However, on our lighter soils some growers were managing to spray this week.
Phoma: this disease has increased, easy to find but barely at threshold levels. In current weather conditions (mild and moist) expect levels to increase. Timing of fungicide not too critical all crops are well advanced and as such at lower risk from stem canker. Aim to use one fungicide application only this autumn. Expect to reach threshold levels in mid-late October in Norfolk will apply Proline mainly tank mixed with an aphicide.
Light Leaf Spot: none seen so far.
Flea beetle: no longer an issue very little fresh shot holing and crops well past the vulnerable stage.
Slugs: crops now past the slug vulnerable stage.
Cabbage root fly: no further cabbage root fly damage.
Aphids: very easy to find wingless aphids in rape this week at the bottom of the canopy on underside of lower leaves. Aphids were all range of colours green, orange, brown, black- not confident how many are Myzus persicae but I expect a proportion are. If not already done so now applying Plenum + methylated seed oil or Biscaya.
Volunteer control: no crop effects seen from Centurion Max. Most fields have had two foliar graminicides. Waiting for soil temperatures to drop before making Kerb applications for blackgrass- only needed on a few fields. Many of our lighter soils in a mixed cropping rotation with plenty of spring cropping and ploughing are blackgrass free. Planning some Astrokerb applications for poppy control. Poppies have emerged through Novall. There was an early flush probably due to the dry conditions and now a new flush of tiny cotyledon poppies are just coming through. Astrokerb will also help with Brome control. Plenty of hedge mustard (not a problem where we plough) on some light fields. We have not used Centium on these v light soils due to crop damage risk.


East Midlands. Forward crops at 8 leaves and full ground cover with later crops at 3-5 leaves but in some cases vary between cotyledon and 3 leaves in the same field where dry soils restricted germination.
Phoma: all crops remain clean so far.
Flea beetle: all crops now away with no problems.
Aphids: numbers remain low with only a few winged aphids found.
Slugs: damage levels remain low with just a few isolated cases where late drilled and slow growth in dry conditions.
Weed control: Centurion Max working well but a couple of crops where some blackgrass plants have grown through it with tillers affected but not main stem – these are not big plants either – resistance starting? Has anyone else seen this.


West Midlands. Growth stages varies from 2 true leaf (late sown or late germination due to dry seedbeds) up to 6-8 true leaves. Some farms with extremely thick lush crops, most farms have had very good establishment and will need a cold winter to check the current rapid growth.
Phoma: more crops now with trace levels.
Flea beetle: no signs of further damage.
Aphids: a very mixed picture with some crops at threshold and others with none at all. Parasitised aphids are quite common.
Slugs: most crops now seem to be OK, even those that are late coming through, some thin patches on heavy land crops but not so thin they won't make a crop.
Weed control: Fathen coming through pre ems on light land.


North East. Crops establishing well across all fields. Growth ranges from 1 to 5 leaves.
Phoma: occasional spots on susceptible varieties, forward crops.
Flea beetle: some low level activity.
Slugs: low levels of activity only.
Pigeons: beginning to flock.
Weed control: pre –emergence herbicides showing effective start so far.


Winter Barley.


South: all drilled winter barley crops now emerging to 3 leaves – still a few fields left to drill.
Eastern: Most crops are in and a lot emerging. Most forward crops at GS 11.
West Midlands. 95% of the crop now in with most forward crops at 3 leaf stage. Managenese deficiency starting to appear on early sown light land crops.
East Midlands. Most crops at GS 11-12.
North East: Drilling to GS12.