: A week of big fluctuations in diurnal temperature ranging from 0 to 21 degrees. Heavy dews have kept crops wet in the mornings which will have benefited Septoria development. Reports suggest that other disease have declined over the last week; brown rust and mildew have not developed. Pollen beetle have been out in the sunshine but many crops remain below threshold levels and as temperatures are forecast to fall most crops may not need treating. Most winter wheat crops are at final leaf 4 emerging with only the most forward with final leaf 3 emerging, this puts crops about 10 days ahead of normal.
Pollen beetle: new thresholds for control
Winter wheat: Disease at low levels Rain needed
: New thresholds proposed for pollen beetle control in oilseed rape suggest that the thicker the crop the lower the threshold per plant is for controlling pollen beetle, for the HGCA information sheet see: http://www.hgca.com/document.aspx?fn=load&media_id=7698&publicationId=8521
Winter Oilseed Rape
South East: About 20% of crops now at yellow bud to early flowering with the majority still at green to yellow bud stage. Crops look even and well.
Phoma: no significant renewed spotting seen to date.
Light Leaf Spot: was being found widely at around 10-20% infection levels in most crops/varieties in last two weeks and particularly those that only had one autumn Phoma/PGR spray applied.
Pollen beetle: all crops still below threshold levels.
Weed control: most crops beyond the growth stage for further weed control.
Eastern Counties: Most forward crops now coming into flower, growth has been rapid over last two weeks. Others moving through stem extension most receiving growth regulator this week, rates for light soils especially have been cut a little due to dry weather. Trace elements now applied.
Light leaf spot: remained at low levels none on upper leaves, recent conditions have not been conducive to spread of this disease.
Pollen Beetle: moving into crops but not yet at threshold levels. Some crops are coming into flower others will soon be doing the same. Backward crops or pigeon grazed areas may need attention.
Weed control: all applications completed.
East Midlands: Crops are growing rapidly and in most crops flower buds are now showing above the crop.
Light Leaf Spot: just odd pieces but nothing of concern yet.
Pollen Beetle: levels still remain low and with cooler weather forecast not expecting to have to treat crops.
West Midlands: Crops have moved on in the last week and some are now at early flowering. The majority are at green to yellow bud stage.
Phoma: no new infections.
Light Leaf Spot: very low levels which have not developed.
Pollen beetle: so far only a few crops have reached threshold level and these tend to be in the south of the region. Temperatures are dropping back now and with a cooler week forecast no treatments are expected.
Weed control: all herbicide applications made.
North East: Most crops at green to yellow bud, but a few have enough flower to be predominantly yellow now. Crops have good colour and grew very quickly during recent warm spell. They are at least 10-14 days ahead of last year.
Light Leaf Spot: a few lesions can be seen in crops now but the level is not causing concern.
Phoma: no further infections seen.
Pollen Beetle: numbers are building now, but so far none been seen at threshold levels for control being required. Will continue to monitor crops until they come into flower.
Weed control: all herbicide applications made.
Yellow rust in Oakley
South East: One particularly precocious crop of Gallant now has final leaf 2 emerging. Fortunately this is the exception with most other crop it is final leaf 4 emerging to fully emerged.
Brown rust: levels have dropped off despite the warm spell and can only conclude that the frosts in February did a better job than expected.
Mildew: with very little sign to date of any fresh pustules.
Yellow rust: no foci or leaf pustule stripes seen, but on untreated trails Oakley has quite high levels of infection.
Septoria: most lower leaves now completely senesced due to Septoria infection.
Eyespot: quite a lot of stem based browning now appearing in many September/early October sown crops.
Weed control: cleavers and wild oats growing well at the moment.
Eastern Counties: Mid September sowings of wheat are pushing through first node visible (GS31). You can find the tip of leaf 4 emerging on the main stem of forward plants. Unless a field is exceptionally forward, it should be unlikely to find leaf 3 emerged on say 80% of the crop until were into the week after Easter.
Brown rust: levels have declined recently.
Yellow rust: quite a lot of rust in Oakley and Robigus, low levels in Viscount.
Mildew: the more backwards crops showing quite a lot of mildew.
Eyespot: low levels in very forward crops.
Weed control: the mild winter has given rise to more cleavers this year than usual. Good autumn control of blackgrass but some cases with resistance. Also where cloddy, dry seedbeds some poor control from pre - ems.
East Midlands: Forward crops at GS 31 with final leaf 3 just emerging and concerned that there will be a long period between traditional T1 and T2 fungicide timings on these crops.
Brown rust: none seen.
Yellow rust: easily found in Oakley but not much grown. Gallant, Duxford and Solstice remain clean.
Mildew: levels remain very low to non existent and seems to have dried up.
Septoria: older leaves dying off in dry conditions but plenty of potential infection.
Eyespot: lower leaves dying off and in drier conditions there is less penetration.
Weed control: some larger flushes of cleavers.
West Midlands: Crops range from GS21 to GS31. T0 fungicide sprays are going on where needed. Some drought stress signs beginning to show on light land crops and tiller death obvious in these crops. Still no sign of rain and after a warm dry week these crops are beginning to go backwards.
Brown rust: none seen.
Yellow rust: still only traces in Oakley and Conqueror. No new infections seen.
Mildew: levels have declined in the last week and new growth is clean.
Eyespot: some lesions in early drilled crops but not developing.
Septoria: lots of septoria in the base of many crops.
Weed control: some large cleavers and wild oats about.
North East: Most wheats at GS 30, but some of the most forward crops at GS31, notably Duxford. No rainfall again over last 7 days. Crops look fine , but they have a large leaf canopy now and under the current high temperatures will be taking up a lot of moisture daily. Every day there is no rain, is another day closer to crops starting to suffer.
Brown Rust: low levels seen in the most susceptible varieties, such as Duxford and Grafton.
Yellow Rust: most crops were sprayed just before a severe level of infection developed. For a few the application was a bit late and these have yellow areas visible now where there is a lot of dead leaf. This should be transitory as new leaf develops over the next couple of weeks.
Mildew: only the most resistant varieties are clean such as Warrior and Viscount. All the rest have varying levels of infection.
Eyespot: more lesions penetrating the outer leaf sheath seen this week, but the dry conditions are reducing the risk of severe symptoms developing before the T1 timing.
Weed control: Cranesbill is the most common broad leaved weed, and there are some severe infestations.
South East: Crops still mostly range in growth stage from GS29-30
Brown rust: pustules still very evident in crops of Volume. No BYDV symptoms seen yet but reports of damage seen in the south west.
Eastern Counties: Most crops have at least 4 tillers. Most forwards are up to 7 or 8 tillers and just below wellington boot height. Some looking as though could lodge
Net-blotch: at treatable levels in some varieties such as Flagon and Cassata
Brown rust: present in Carat and Pearl.
East Midlands: Generally crops at GS 30 and about to get their first fungicide. Levels of mildew, net-blotch and Rhynchosporium all remain low in the dry conditions.
West Midlands: Crops range from late tillering to GS 30 another week before T1 fungicides are needed. Very little Net-blotch or Rhynchosporium and no brown rust. Light land crops are suffering now in the drought and there is signs of take-all in these crops.
North East: Most forward crops at GS 30-31. Crops look fine so far. Only low level of diseases now following early application of fungicide.