Changes to the way pesticides are approved in the EU have concerned the UK industry since they came into force in 2011, but fears are rising as a key group of fungicides face the threat of a potential ban.

There is much speculation on the outcome, but if all triazoles were lost in a worst-case scenario, wheat yields would be up to 12% lower, according to experts.

This is because triazoles are at the heart of UK fungicide programmes, controlling key cereal diseases such as septoria, and yellow and brown rusts. Oilseed rape and minor crops would also be severely affected.

The problem

Up to 2011, the EU had used “risk-based” assessments in the approvals process which takes sprayer operator exposure into account, but the problem is that the new approach uses hazard-based “cut-off” criteria instead.

This means if a product has a particular characteristic, it can no longer be approved at European level, even if exposure under realistic conditions in the field means there is negligible risk to the user, explains BASF’s John Peck.

Endocrine disruption is one of the “cut-off” criteria, which is why triazoles, the largest class of fungicide chemistry, is at risk of being lost to growers.

But there is no regulatory definition of what an endocrine disrupter actually is, although the Commission is required to have one by the end of 2013, says Mr Peck.

A temporary definition is being used as an interim measure, but the final definition will be crucial to determine where the axe will fall and which triazole fungicides will be lost.

“Depending upon where the line is drawn, there could be severe consequences for UK and EU farming. We could lose most, if not all of the triazoles when they come up for renewal,” he warns.

Any hopes of a derogation within the legislation cannot be relied upon, he says, as the commission indicated this would be in exceptional circumstances.

The commission has its own views on where the cut-off could be, but has considered proposals from member states.

The UK and Germany put forward a joint proposal that keeps the cut-off at the more reasonable end of the scale, allowing valuable products to be retained, says Bayer’s Julian Little.

However, not all member states are in agreement. The Danish proposal is much more draconian and would take out potential endocrine disrupters rather than taking a more pragmatic view, he adds.

“There is a lot of activity going on between member states and the commission to get the Anglo-German proposals adopted more widely.

“The Crop Protection Association and the European Crop Protection Association are taking a lead on this and manufacturers are working with them to make sure the message gets right across the food chain,” he adds.

What next?

Next month, the European Food Safety Authority is due to report back to the commission with its view on a draft definition of an endocrine disrupter. It is hoped that it will fall closely to the UK proposal of a more sensible risk-based approach, says Don Pendergrast of the NFU.

In the meantime the NFU is trying to ascertain from other farmers’ unions what the view is across the EU and where other member states stand.

It will become clearer as 2013 progresses, but with the UK government firmly supporting a more reasoned approach, it will be within Europe where the battle is and where pressure needs to be applied. With the first quarter of 2013 being a key timing, now is a good time for growers to get out there and apply pressure on their MEPs, stresses Dr Little. “Representatives in the EU parliament need to be made very clear what the consequences of taking the wrong decision would be.”

“We cannot afford that at a time of rising food prices and food security. This is a situation that cannot be allowed to happen.”

Potential impact

If and when active ingredients are revoked it is anticipated (but not definite) that they will be phased out according to their renewal date.

The potential impacts of triazole loss are largely speculative because we don’t know which ones will go, all we do know is that there will be fewer triazoles around in the future, says NIAB TAG’s Bill Clark.

On top of this, their activity on septoria continues to decline and losing some products would be counterproductive, he explains. “EU legislation is treating triazoles with a broad brush, but we know triazoles are not all the same.

“The more you have, the better anti-resistance strategies we could have.”

Whichever products remain will end up being used in more complex, two- and three-way mixtures together with different triazoles used at different times of the year to combat the resistance issue.

“We will be using more protectant materials, such as chlorothalonil, mancozeb and folpet, which alone don’t look impressive, but will give better disease control.”

Frequency of sprays would increase, with a need for an additional application at GS33 to protect leaf 2 due to the reduced eradicant activity from the GS39 timing.

So by removing some of the pesticides, growers will need to spray more frequently, thus using more fuel, leaving a higher carbon footprint and costs may go up and efficacy will go down, he adds.

Losing triazoles would also expose the SDHI’s and with no protection they could be lost within two to three years. The chance of getting a new eradicant fungicide is slim in the next decade, says Mr Clark.

“If the ruling translates into all triazoles, we couldn’t grow the current varieties we have and would be looking at 10-12% yield loss in wheat across the UK and Europe.”

The knock-on effect of increased prices has a moral implication, whereby the UK would be OK, but countries importing wheat from Europe would be at a disadvantage, he concludes.

More than a spot of trouble for rape crops

The biggest challenge in oilseed rape would be controlling light leaf spot, as only the triazoles are used to combat the disease, says ADAS’s Peter Gladders.

“We don’t have many resistant varieties to counteract it at the moment. Even so, with high disease pressure, resistant varieties are put under strain because there is nothing to bail them out. Also light leaf spot resistant varieties are phoma susceptible, so exposing crops to a canker epidemic.”

It may be possible to bring in other chemistries, utilising SDHI and strobilurin mixes, but because of their single site mode of action they are high-risk strategies, he says.

Oilseed rape would become more difficult to grow in Scotland with the pressure reducing further south.

Yield losses from light leaf spot could be up to 1t/ha without triazoles, and phoma anything from zero to 0.5t/ha depending on varietal resistance.

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