« Bern's winegrowers spray and spray » – this was the headline of the «Berner Zeitung» newspaper on 29 July. One of them is winegrower Hubert Louis. He works on the vineyards of the city of Bern above La Neuveville on Lake Biel and can tell you a thing or two about how essential the use of crop protection products is in such extreme weather conditions. The «Berner Zeitung» sums it up: «Hubert Louis doesn't have to look far before he can show the damage to his vines. This year, he decided not to use pesticides on a 15 metre strip as a trial. The result: not a single healthy grape is growing on these vines. Instead, you can see brownish discoloured leaves and dead berries.»

According to the report, one often hears the statement that viticulture is not possible without pesticides when talking to winegrowers. Crop protection products are also essential for organic farms. However, they do not use all the modern crop protection products available on the market, but only spray products that are authorised for them, such as copper or sulphur.

Organic winegrowers must spray 15 times per season

However, spraying copper is not harmless: the active ingredient, which is sprayed preventively in organic viticulture, is a heavy metal and pollutes the soil. In addition, it is immediately washed away again when it rains, which means it has to be reapplied. The consequence: depending on the weather, organic winegrowers are forced to spray up to 15 times per season. As the «Berner Zeitung» reports, this is the case this year. However, losses cannot be prevented: «We expect 20 to 30 per cent less harvest than last year», says Louis. Downy mildew is responsible for this poor forecast. This is a fungal disease that spreads through the grapes and foliage in damp weather.

While organic farmers are only allowed to spray the products authorised for them, conventional winegrowers have more room for manoeuvre. They are also allowed to spray semi-systemic fungicides, whose active ingredients protect the plant from the inside out over a longer period of time.

On Stephan Martin's vineyard in Ligerz, which has 3.6 hectares of conventional vines, semi-systemic fungicides are used in addition to the organic active ingredient groups. Downy mildew was a major problem for the winegrower at his «Weingut am Stägli» vineyard. However, thanks to treatment with conventional plant protection products, the situation is no longer as dramatic in years with high rainfall such as this year or in 2021. He only had to spray the Pinot Noir nine times this year – only once more than the year before.

Conventional products certainly have their advantages: The pesticides are washed off less and consequently farmers have to spray less often. Organic winegrower Hubert Louis also has to admit: since he converted his farm to organic, diesel costs have risen sharply. But more passages also mean more CO2 emissions and more soil compaction.

Things go downhill without crop protection

But it wasn't just all the rain, but also the warm days in February and March that affected the winegrowers this year. Farmers had to fear for their harvest as the vines sprouted earlier, increasing the risk of frost. However, the situation is also precarious for other crops. The heavy rainfall favoured tuber blight and destroyed the harvest for many potato farmers. The numerous losses have put a spanner in the works for many farmers: 300 hectares of potato fields have already had to be abandoned.

The reason for the misery is obvious: wet weather favours fungal diseases – in the case of the Bernese winegrowers it is downy mildew. The impressive examples of farmers discussed in the «Berner Zeitung» make it clear how essential crop protection is and how much crop loss can occur in difficult growing years without plant protection. It is particularly important that farmers also have access to modern products. Only if they have sufficient crop protection products at their disposal can the harvest be protected even in a miserable growing year.

However, crop protection in particular is currently being neglected in Switzerland: at the end of 2022, around 700 crop protection products were awaiting authorisation. Some of them for years. The sluggish authorisation process and the mountain of pending applications prevent efficient crop protection with modern products. There is therefore a lack of options for combating pests and plant diseases. There is also a risk of resistance if farmers no longer have access to a sufficiently wide range of products. If plant protection is neglected, this leads to «food waste» in the fields, which experts refer to as «food loss». Farmers are literally «left out in the cold».

Even fungus-resistant varieties are affected by the rain

But how can crop losses be minimised? Do we need new varieties as a solution? Fungus-resistant varieties (PiWi), which require significantly fewer plant protection treatments, could provide a remedy. In the canton of Bern, 11 per cent of the vineyard area is already planted with these varieties. In this wet year, however, even these varieties were not immune to the devastating consequences of the heavy rainfall. Matthias Rindlisbacher, who also has a vineyard with PiWi varieties in Wyssloch in the city of Bern, provides proof of this: «We will probably be able to harvest a third of the expected quantity».

Despite the use of crop protection, the farmer reports in the «Berner Zeitung» about massive losses even with the PiWi varieties. Rindlisbacher's example makes it clear that new varieties are not a panacea – but they can be an important tool alongside modern crop protection.

New breeding technologies such as CRISPR/Cas are very promising in this context, even if they are not mentioned in the Berner Zeitung. The new technologies make it possible to breed disease-tolerant plants more quickly than with conventional breeding. This means that popular varieties that have broad consumer acceptance can be made resistant more quickly and easily than if consumers have to get used to completely new varieties. This is because consumers know what to expect. This is the case with a Chasselas or Pinot Noir, but not with a completely newly bred variety.

Unfortunately, applied research and local plant breeding are currently being held back by restrictions. Politicians and authorities are acting timidly and are sticking to the outdated Genetic Engineering Act, for example. As a result, research into innovative breeding is increasingly taking place elsewhere instead of here in Germany. If this continues, Swiss agriculture is in danger of missing out on this global wave of innovation. Harvests will continue to decline and imports will increase. Is this in the interests of consumers?