Budgeting fungicide spend in wheat crops this spring isn’t easy. Grain prices of around £100/t currently for harvest movement of wheat won’t encourage many growers to think about increasing fungicide bills, probably just the opposite.

But crops, in general, look promising, full of potential. Experts are also worried about potential high disease pressure with a high proportion of rust-susceptible varieties in the ground, and a seemingly more aggressive race of yellow rust on the rise.

Don’t discount septoria either – it remains the number one yield-robbing disease, and has to be protected against.

That suggests a difficult balancing act between spending what you can afford, and what you need to produce the best disease control and return.

Last year, according to industry data, the average cost of fungicide programmes rose from the previous season by £4/ha to £76/ha. But it masks a huge variation with some growers spending only £35-45/ha on some crops to other programmes costing over £100/ha.

Not surprisingly, BASF‘s Peter Hughes believes those growers spending below average are missing a trick. Fungicides are a hugely responsive input, he says.

He points to trials at Rawcliffe Bridge in Yorkshire. Nine different fungicide programmes, chosen by representatives from distributors and AICC agronomists, were sprayed across 24 varieties.

The average yield response compared with the untreated across all varieties from all programmes was 3t/ha. Yellow rust susceptible varieties, such as Oakley (7t/ha), Robigus (6t/ha) and Solstice (5t/ha) gave huge responses. But even the relatively disease-resistant Warrior gave over 1t/ha response to the programmes. “It pays to spend on fungicides,” he insists.

And investing more produces better returns, the trials suggest. A relatively robust four-spray programme of triazole fungicides plus some chlorothalonil (see table, programme 1) at T0 and T1 costing £76/ha gave an impressive 11.48t/ha across all 24 varieties – an increase of just under 2.5t/ha over the untreated.

But increasing spend by £8/ha, swapping in Ennobe for the triazoles at T1 and T2, and adding Tracker added an extra £23/ha to the bottom line.

And probably more importantly with this season’s perceived rust risk, adding two strobilurin fungicide sprays, in the form of Envoy and Firefly at T2 and T3, further increased yields by 0.5t/ha. The programme at £93/ha cost £9/ha more than programme two, but returned an extra £39/ha.

A lot of growers could make more return from their land by making better use of fungicides, Mr Hughes says. “There is a clear correlation – the better programme you use the better return you get.”

Prime Agriculture’s Marion Self says a typical fungicide budget for a first feed wheat on medium land ranges between £75-90/ha this season, with a lot spending £82-85/ha.

That represents around 20% of the variable costs of growing a crop of wheat this season, 5% more than last season, mainly due to cheaper fertiliser this season reducing the proportion required for that key input.

“It shows that fungicides are a very important input, and you need to choose wisely,” Ms Self says. “But with wheat at £100/t, you only need a 0.85t/ha response for the programme to pay for itself at £85/ha.”

Growers should expect at least that response in most years, according to historical data from The Arable Group‘s Morley site. In the past 23 years, in only four years has the response to the three- or four-spray commercial fungicide programmes been less than 1t/ha – the last of which was 2001 – and only in two years has the response been significantly less than this year’s break-even figure.

“On average the response has been 2.5t/ha. They are a big input, and you get a big return. But every element must pay,” Ms Self says.

This year that is likely to include a T0 spray, she notes. “There won’t be many crops that won’t receive one – I think we can justify that spend.”

That’s even though the perceived rust threat is, perhaps, diminishing with every week of cold weather.

Back in the autumn, after quite a lot of early drilling, and above average autumn temperatures, there was some concern about the yellow rust susceptible varieties in the ground, she admits.

But three months of below average temperatures have reduced the immediate threat. “It should have done a lot for keeping it down, although it doesn’t take much for it to kick off, so growers should remain alert.”

That’s particularly the case for growers with a large area to cover, or those with off-lying land. “Timing is critical to controlling rust.”

Make a plan to deal with rust, she urges growers. “Look at the susceptibility of your varieties and drilling dates, and come up with a schedule and priority list for spraying through the season.”

If rust does become a serious threat early in the season, typical budgets for each spray (see chart) might need to be adjusted. “You might then spend more on a T0 triazole, and consider using a strobilurin at T1.”

But overall spend need not go up too much, she stresses. “You might be able to save a little at T2 depending on the season and septoria risk.”

Planning fungicide strategies for the spring? Watch Andrew Ward and Marion Self discuss options for Oakley and other rust-susceptible varieties at www.fwi.co.uk/oakley

Rust Watch

Seen any yellow or brown rust yet? Be the first to report a sighting on FWi’s Rust Watch page or let others know your crops are clean and still be in with a chance of winning a weather station. Visit www.fwi.co.uk/rustwatch and fill out the simple form regularly to update our rust watch map

CASE STUDY

Lincolnshire grower Andrew Ward is budgeting around £90/t for his fungicides on first wheats and £96/t for second wheats for 2010.

It’s an £8/ha increase on 2009, but mostly due to expected price increases rather than any major changes in the programme, he says.

That kind of spend is justifiable based on his expected costs of production. Thanks to an almost incomparable knowledge of his business costs, including all overheads and fixed costs, he expects them to range from £60/t for first wheats after oilseed rape to just over £70/t for second wheats.

He’s helped by being able to use sewage sludge on quite a lot of crops, which cuts his fertiliser costs by over 50%. Where he can’t use sewage sludge in the rotation it adds around £7/t to first wheat production costs, and £10/t to second wheats.

The low costs are driven primarily by expectations of high yields – 12t/ha for first wheats and 10.5t/ha for second wheats. Both represent a 0.2t/ha yield increase on 2008’s record harvest.

But even a drop in yield to 10.3t/ha, the average yield in 2009, would only see the cost of production rise by £10 to £70/t for first wheats.

More worrying would be a repeat of his lowest ever second wheat yields of 7.4t/ha. An extremely wet autumn followed by a dry spring, where fertiliser was not taken up very quickly and loss of tillers was to blame, he says.

A similar yield this year would drag the cost of production up to just over £100/t – very close to the current grain price. “But the potential of the crops coming out of the winter looks every bit as good as 2008.”

In both seasons he used very similar fungicide programmes (see table), but trials on the farm comparing Ennobe at T1 with Tracker in second wheat have convinced him to make a switch on at least some of the farm.

In the trials, 1.25 litres/ha of Ennobe yielded 1.27t/ha more than Tracker in one field, and 0.5 t/ha in a second. “I do the trials to see where to alter things. I’m a bit reluctant to change wholesale, but will probably switch 30% of the second wheat into an Ennobe programme.”

A second set of trials comparing Proline at T1 with Brutus failed to see any difference. “Brutus looks like it might be more suited to T2, so I will try that this year.”