16 April 2012: Winter oilseed rape still reluctant to come into full flower as night frosts slow growth. This could prove to be a very protracted flowering period for this crop. Winter wheat crops have also slowed in growth. The most forward crops have final leaf 2 emerging which is very early, however, the majority of crops have final leaf 3 emerging and consequently will soon be ready for the first main fungicide. Septoria levels are causing concern in some areas with final leaf 5 showing signs of infection. Yellow and brown rust have mainly been kept in check by the cooler nights and T0 fungicides.
Sclerotinia risk: increases with recent rain
Pollen beetle: threat declines as crops flower
T1 fungicide: timing in winter wheat
Winter Oilseed Rape
Sclerotinia on stems of oilseed rape
(courtesy of Farming Online)
South East: All crops now between yellow bud/1st Flowers just visible to early flowering. All nitrogen applications have now been completed.
Phoma: no significant renewed spotting seen to date.
Light Leaf Spot: no new infections seen.
Sclerotinia: conditions are potentially conducive to the germination of sclerotia, particularly under thick canopies ? as crops start flowering.
Pollen Beetle: only a few later developing crops located in smaller and sheltered fields have needed treating this year.
Eastern Counties: Just a few fields in full flower, Camelot is early; but due to the cooler temperatures flowers are opening very slowly. Several fields of DK Cabernet still at late yellow bud. Seeing a little frost damage to buds, especially on DK Cabernet.
Light Leaf Spot: remained at low levels none on upper leaves, recent conditions have not been conducive to spread of this disease.
Sclerotinia: wet conditions increase the Sclerotinia risk, planning the first application for early/mid flowering.
Pollen Beetle: the cool weather meant that pollen beetle activity slowed right down and numbers in all the crops have remained low.
East Midlands: Most crops starting to flower with a few having a good cover of flowers.
Light Leaf Spot: just odd pieces but nothing of concern.
Sclerotinia: Sclerotinia sprays aimed at early flowering.
Pollen Beetle: most crops beyond stage were control needed.
West Midlands: All crops now at green to yellow bud stage to early flowering. The colder days over the last week have put crops on hold so many are very slow to come into full flower. However, some fields now have a good overall yellow appearance to them, and some petal fall can be found. Most forward crops are Cubic, Excalibur and Vision particularly where they are on lighter land.
Phoma: no new infections.
Light Leaf Spot: very low levels which have not developed.
Sclerotinia: rain over the last few days has increased the risk of disease.
Pollen Beetle: majority of crops now out of danger.
North East: The recent warm spell has brought a lot of crops of Excalibur and Ex-Power into flower. Cabernet and Compass are still at green to yellow bud.
Phoma: no further infections seen.
Light Leaf Spot: a few lesions can be seen in crops now but the level is not causing concern.
Sclerotinia: most crops being grown in fairly tight rotations so assume all are at high risk of infection.
Pollen Beetle: crops coming into flower are no longer at risk, but above threshold numbers have been seen in a few crops still at green-yellow bud.
(courtesy of Farming Online)
South East: Crops continue to develop quite rapidly despite some frosty nights that have ?put the brakes on?. Crops now range from GS30-31 (late October+ sowings) to stem extension GS 31-32+ (September sowings) with up to Leaf 3 fully emerged and Leaf 2 up to 25% emerged on main shoots of Gallant/Solstice. Have now had 30mm of rain in last week, so any worries about soil moisture deficits abated for now at least ? lets hope the weather does not now get stuck in too much of a rut! Soils now wet enough to properly ?wash? nitrogen into root zone.
Brown Rust: odd pustules can be found in thicker crops and more particularly in September sown crops of Claire, Target and Solstice.
Mildew: since the frosts in February most crops remain free of any re-infection to date ? only exception is a few lush and forward crops of Gallant/Solstice.
Yellow Rust: no foci or leaf pustule stripes seen, but remain vigilant particularly on varieties that may be prone to the Warrior race.
Septoria: most lower leaves now completely senesced due to Septoria infection, with infections highly visible on leaf 5 of all September sown crops of Gallant/Solstice in particular.
Eyespot: quite a lot of stem based browning now appearing in many September/early October sown crops.
Weed Control: spring headland and field applications for brome control mostly completed.
Eastern Counties: Leaf 3 is emerging on forward fields. Gallant and Humber are a little ahead of Solstice and Diego, with Oakley still a half leaf behind. T1 timing will be towards the end of the week beginning 16 April.
Brown Rust: no new infection seen since application of T0 fungicides.
Mildew: the more backwards crops showing quite a lot of mildew.
Yellow Rust: no new infection seen since application of T0 fungicides.
Eyespot: more eyespot symptoms seen this week.
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.
East Midlands: Forward crops have leaf 3 appearing but on average crops are at GS 31+. Some BYDV being seen but so far not at high levels. Nitrogen has gone on in the last week or so and with the rain some crops starting to look a bit hungry, but on the whole crops look plenty green enough.
Brown Rust: none seen.
Mildew: levels remain very low to non existent and seems to have dried up.
Yellow Rust: no new rust seen but T0 will soon run out of steam so T1 will need to be timely.
Septoria: crops slowing down with cooler weather, T1 being about 5-7 days away and with disease pressure high triazole rates will be kept up on the whole.
Eyespot: levels remain steady.
Weed Control: Fumitory appears to be the crop of the moment but easily controllable.
West Midlands: Colder conditions of late have put many crops on hold. September sown crops have leaf 3 emerging or fully emerged in the most forward crops, but for many the T1 applications are still seven to ten days away. Late September or October sowings still have final leaf 4 as the most recently emerged leaf. Finally a bit wet out there but suspect that tramlines are so well established now that it's unlikely any significant ruts will form.
Brown Rust: none seen.
Mildew: levels have declined in the last week and new growth is clean.
Yellow Rust: no new infections seen.
Septoria: lots of Septoria in the base of many crops.
Eyespot: some lesions in early drilled crops but not developing.
Weed Control: flush of weeds have come through in these last few days of rain.
North East: Most wheats at GS 31. The local clay soils have retained enough moisture for wheat crops not to be showing any drought stress despite a 26 day period with no rainfall. There have been heavy dews most nights that have helped and a forecast of significant rainfall started this afternoon (April 3rd). Most crops look fine, but some are very ?ginger? due to severe leaf tipping. This is most obvious in forward first wheats. In some of the Oakley it is partly due to the dead leaf left after the Yellow Rust has been controlled, but in others such as Invicta it is probably a result of the sharp frosts a couple of weeks ago, just as the T0 fungicide was being applied.
Brown Rust: low levels seen in the most susceptible varieties, such as Duxford and Grafton, but well controlled so far by the T0 fungicide.
Mildew: only the most resistant varieties are clean such as Warrior and Viscount. All the rest have varying levels of infection.
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.
Septoria: fairly high levels seen on older leaves of most forward crops, but development halted for now by T0 fungicide.
Eyespot: more lesions penetrating the outer leaf sheath seen this week.
Weed Control: cranesbill is the most common broad-leaved weed and there are some severe infestations.
South East: Crops have moved quickly in response to generally good growing conditions and now range in growth stage from GS31-32 with leaf 2 emerging in most forward crops. T1 fungicides have been applied to Cassata/Cassia last week and planned for early next week in the slower developing 6-row Volume. Late PGR applications will need completing on more advanced crops in next two weeks. All Nitrogen applications now completed.
Brown Rust: still very evident in many crops and getting active again. Have seen one crop of Volume where only top 2 - 3 leaves are green and rest have largely senesced due to brown rust.
Eastern Counties: Forward crops at GS 31 and quite tall.
Brown Rust: present in Carat and Pearl.
Net Blotch: at treatable levels in some varieties such as Flagon and Cassata.
East Midlands: Generally crops at GS30 and about to get their first fungicide. Levels of mildew, net-blotch and Rhynchosporium all remain low in the dry conditions.
West Midlands: Quite a few crops affected by Rhizoctinia barley stunt confined to the lighter patches of fields. Most are smallish areas worst is about 2 hectare patch (approximately 20% of fields have this to a greater or lesser degree).
North East: Most forward crops at GS 31. Crops look fine so far with only low level of diseases following early application of fungicide.