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“We’re in a yellow rust area growing a lot of yellow rust-susceptible varieties, so Adexar’s strength against the disease made it our T2 spray of choice last year and we’re likely to go with a similar fungicide policy again this year.”

That policy centres around a robust four-spray programme featuring a triazole + chlorothalonil at T0 and T1, followed by SDHI chemistry at T2 in the form of Adexar on yellow rust-susceptible varieties alongside Aviator on other wheats. Fungicide programmes are normally finished off with a triazole/ strobilurin at T3.

Last season Mr Howell applied Adexar at 1.25 litres/ha, in mix with 1 litre/ha of chlorothalonil and was very happy with how it performed, although he acknowledges disease pressure was low last year.

“I like the fact that BASF don’t have a problem with tank-mixing Adexar with chlorothalonil. We do this to help keep on top of septoria and it also works from a resistance management point of view by widening the range of actives we’re using.”

Mr Howell did try a split-field comparison between Adexar + chlorothalonil and Aviator last season and while both products worked very well, he says there may have been a slightly higher yield from the Adexar, but acknowledges this may have been down to the natural variation in his on-farm comparison.

“There was a very small yield advantage from the Adexar mix, but with the extra cost from the chlorothalonil, they were equal financially.”

Given the potential for higher disease pressure this spring, Mr Howell says he is considering using SDHI chemistry at T1 as well as T2 this year, but the final decision will depend on disease pressure nearer the time.

“If we can get all of our T0 sprays on at the optimum timing, it may allow us to potentially make some savings at T1 and avoid the need for an SDHI then. We would still go with SDHIs at T2 though.”
Wheat varieties in the ground this season at Proctor Bros (Long Sutton) Ltd include Santiago, Cougar, Leeds and Kielder, in rotation with oilseed rape, spring beans, marrowfat peas, potatoes and sugar beet across the 1,800ha (4,500-acre) farm.

Proctor Bros (Long Sutton) Ltd, Lincolnshire
•    Area: 1,820ha (4,500 acres)
•    Cropping: 50% wheat, oilseed rape, spring beans, marrowfat peas, potatoes, sugar beet
•    Wheat varieties for 2014 harvest: Santiago, Cougar, Leeds, Kielder

Putting efficacy first

Cambridgeshire grower Chris Ascroft also believes Adexar has strong efficacy against yellow rust, as well as septoria and other key diseases.

Adexar was the main T2 fungicide choice last year at Wilbraham Farms between Cambridge and Newmarket and is likely to take centre stage again this spring due to the large area of Santiago in the ground (rated 4 for yellow rust on the HGCA Recommended List).

“Yellow rust is certainly the disease of the moment,” Mr Ascroft says “But while there’s a lot of talk about it, fortunately we haven’t really seen much in the field yet, so if we can use a product that’s strong on yellow rust and has a good broad spectrum of disease control, it’s the way forward.

“The Opus [epoxiconazole] in Adexar still seems to control septoria well and I also like to keep things simple with the one-can approach,” he adds.
“We choose our fungicide products based on efficacy first and cost second.”

Fungicide strategy at Wilbraham Farms, which has put most of this season’s 300ha of wheat down to Santiago, plus some Panorama on contract farmed land, normally centres around a three/ four-spray programme. This year that means a T0 of Artemis (fenpropidin, prochloraz + tebuconazole) + plant growth regulator, followed by a triazole + chlorothalonil + strobilurin mix at T1 and Adexar at T2.

Rates are varied depending on disease pressure, with Adexar applied at 1.6-1.75 litres/ha last season, largely on its own. “We did add a bit more epoxiconazole on some bad septoria fields, but mostly it was straight Adexar.”

The decision as to whether a T3 is necessary is normally kept open depending on disease risk later in the season, Mr Ascroft notes. “We’re on quite light land and mainly growing feed wheat. If it’s very wet we are likely to use a T3, but if not, we’ll probably get away without using one.”

It is a strategy that certainly seems to have worked last year, when average wheat yields across the farm were nudging 10t/ha (4t/acre), which was well above the five-year average of 7.5t/ha. “For our light soil, that was a really good result, but I think it was probably mostly down to the weather which suited our land.”

Wilbraham Farms, Cambridgeshire
•    Area: 1,000ha (owned and contract farmed)
•    Cropping: wheat, winter and spring barley, HOLL oilseed rape, sugar beet
•    Wheat varieties for 2014 harvest: mostly Santiago, plus some Panorama
•    Wilbraham Farms is also part of the RTK Farming Network - http://www.rtkfarming.co.uk/