West Midland & Wales: General Synopsis: The Beast is Back

16.05.2018

What a difference a year makes. This time last year we were staring down the barrel of a drought, with very high temperatures and rampant yellow and brown rust.

When asked about septoria pressure, 60% of farmers believed their crops were clean of septoria infection. However, even last year our own CuraCrop DNA analysis revealed that 90% of the lower leaves and 64% of the upper leaves were carrying infection just prior to T2.

Scroll forward 12 months and it is a very different story. A very long and latterly wet winter has kept sprayers in the sheds. When it was possible to finally travel in the fields, spring nitrogen applications and grassweed herbicides took priority over T0, so many growers only managed to apply 50-60% of their planned T0 programme.

The weather remained very unsettled up to the key T1 timing.  Recommendations have been rewritten many times, but where no T0 was applied and there is blatantly obvious septoria infection in the crop, the need to get T1 right has been imperative.

Most growers now recognise the importance and benefit of repeated multisite chemistry, particularly chlorothalonil in their programs along with appropriate doses of azole and SDHI. For those that did not get an opportunity to apply a T0 it became imperative to opt for good curative and protective chemistry along with a multisite at T1.

Adexar (Xemium + epoxiconazole) has proven itself over many years, there are no antagonism issues when mixed with a CTL multisite and despite the frenzy of phone calls and what felt like blind panic at times, the advice to stick at 1.0l/ha of each was recommended. After all, the newly emerged leaf 3 was the target and that had clearly not been exposed to bubbling cauldron of septoria lower down the plant for very long.

So T2 is upon us, flag leaves are emerging and despite the late start to spring, crops are pretty much at a similar growth stage to last year, or any year come to think of it.

However, for many the gap between T1 and T2 may not be three weeks, and for some who have only recently applied their T1 it may mean having to go back through their crop as little as 10 days later with their T2.

Recent samples of plants treated with a robust T1, taken on 16 May from our Real Results demonstration farm at Wigmore Grange, have revealed the following disease scores:

Crusoe

Flag leaf, 75% emerged, clean

Leaf 2, clean

Leaf 3, 5% infection

Leaf 4, 30% infection

Leaf 5 dead, 100% infection

Siskin

Flag leaf, 85% emerged, clean

Leaf 2, clean

Leaf 3, 5% infection

Leaf 4, 30% infection

Leaf 5 dead, 100% infection

KWS Barrel

Flag leaf, 30% emerged, clean

Leaf 2, clean

Leaf 3, 5% infection

Leaf 4, 50% infection

Leaf 5 dead, 100% infection

But, for peace of mind, Adexar has the highest 5-star rating of any product on the AHDB fungicide chart, for both yellow and brown rust along with septoria.

So, it’s been a tough year to date, with timings all over the place and septoria pressure very high – the beast is most definitely back and should not be ignored.

Getting the T2 right is critical, Adexar or Librax (Xemium + metconazole) at 1.25l/ha with the inclusion of a litre of CTL should give you the peace of mind that tried and tested chemistry will deliver for you again, not just this year, or last year, but every year.