TRADE AND MARKET I NG Robust is the new trend Peter van Eerdt, Danespo, Berltsum: ‘We must be careful that we don’t lose it all with innovation’ because they can already be harvested before the highest Phytophthora pressure time. However, what you see is that they’ve already contracted a Phytophthora infection and that this actually increases the pressure in later crops. So, from the sustainability point of view, we aren’t solving anything. What I mean by this is that we must be careful that we don’t lose it all with innovation. So I believe that we’re on a roundabout with lots of exits with our breeding activities and that it’s now a matter of choosing the right one. Sustainable and robust, we believe that this starts with the cultivation of nitrogen-effective varieties. What we mean is varieties that use the nitrogen in the soil as efficiently as possible and combine this with good resistance to Phytophthora. Strangely enough, our oldest variety suited to organic cultivation is the best example of this. I’m talking about Sarpo Mira. This variety needs little nitrogen, ripens relatively late and with leaves and tubers that are still highly resistant or even immune. If you’re talking about robustness, then I think – no, I’m sure – that this is the best example.’ ‘With the word robust I make a direct link to sustainability. Everyone sets themselves targets when it comes to sustainability. Except it’s often very different in practice. For example, both the government and the agricultural sector have set themselves the objective of reducing the use of nitrate. However, no one ever asks us whether we have a chips variety for them that needs less nitrate. No, we prefer to have a variety that can grow on pure dung, because that suits most farmers very well. There’s a manure surplus and many potato growers can use it. So they ask for nitrogen-loving varieties. That’s not the same as robust and sustainable. In our perception, a robust variety is one that requires little fertiliser, has several resistances, and stress and drought tolerance. This is why growers are currently working hard on Phytophthora resistance, for example. When it comes to that, they often try to get early varieties that give the highest possible yield in fewer growth days, often combined with high nitrogen inputs. You might wonder whether this is a robust, sustainable development. You often see that these varieties don’t need to have the highest resistance, Harry van de Vijver, Germicopa, Cedex: ‘To over the years‘ ‘Robust with regard to a variety is a combination of good resistance, good yield and stability in all characteristics. Not sometimes very good, for example because the growing conditions in a season are optimal, but a variety that, over the years, gives a continuously reliable result under adverse climatic conditions. The word robust has recently been linked to the bio-covenant, which encourages the cultivation of only Phytophthora resistant varieties in the shortest possible time. Especially when it comes to time pressure, I think we should be careful not to price the potato out of the market. This morning I had a customer who said that he was not happy with the covenant on this point. According to him, this creates the danger of developing varieties with weak resistance which can be grown in relatively large areas quickly, but with the risk of a rapid resistance breakthrough. And then you have a big problem in cultivation and in marketing. I just want to point out that you can’t arrange something like growing robust varieties with the desired resistance in a short space of time. Just look at the breakout of pallida resistance in the Emsland in Germany. It can take years before you find a variety again with a suitable resistance for such a growing area. You’ll lose an important growing area for a long time. As long as we’re not yet able to have varieties available on a large scale with strong resistances such as to Phytophthora, it’s better to choose varieties with reduced susceptibility, which we can continue to use with as little spraying as possible. That’s a more robust approach, I think. If I look at our variety package, 30 Potato World 2018 • number 1 Pagina 29

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