Optimal biodiversity in sugar beet growing
Every year in the Netherlands, sugar beets are grown on around 85,000 hectares of farmland. All of these beets are processed by the Cosun Beet Company. We have joined forces with the Province of Noord-Brabant and Naturalis to launch the Green Circles Circular Sugar Beet Chain. When it comes to sugar beet growing, biodiversity is given considerable attention and opportunity. After all, it is essential for robust and future-proof cultivation, especially with the current climate change.
All sugar beet growers in the Netherlands are members of the Cosun cooperative and deliver their beets to the Cosun Beet Company. They receive support and advice from the agricultural services and IRS, an independent research and knowledge centre devoted to sugar beet cultivation in the Netherlands. This facility is unique in that, apart from sugar beets and chicory (processed by the Royal Cosun Company Sensus), no other crops in the Netherlands have this type of expertise centre. Jurgen Maassen, Information Coordinator at the IRS, explains the advantages this offers. “Since our establishment in 1930, our guiding principle has been that farmers benefit from good advice and guidance - not based on what the producers of seeds and plant protection products say, but on facts. We have our own trial fields, climate chambers and laboratories where we can conduct extensive research into the effects of specific products or the advantages of specific varieties.”
Biodiversity
Another basic principle of the IRS is that in combatting pests and diseases, the population of natural enemies – and consequently, biodiversity – must remain as intact as possible. “Not only is this good for nature, but also essential for crop growing, as fewer and fewer plant protection products are allowed. This makes natural enemies all the more important.”
Beet seeds
The first step to successfully growing crops using as few plant protection products as possible starts with selecting the sugar beet variety. Jurgen explains, “There are different types of varieties, each with its own unique characteristics. For example, some varieties are resistant to certain types of microscopic ‘worms’ in the soil, the yellow beet cyst nematode. So, the presence of these nematodes is always considered when advising growers on the best type of beet seed to order for the next growing season.”
Monitoring and counts
Once seeds have been sown, it is important to be on the lookout for the presence of pest insects – and their quantities. “Naturally, growers do this themselves, but the Cosun Beet Company agricultural services also carries out weekly counts at over a hundred parcels across the country. In doing so, they also establish the number of individuals of a specific species on a predetermined number of plants each week. Their observations can be viewed in maps via the Beet Advice System (BAS) and at www.irs.nl. And if more individuals are observed than the established damage threshold, a warning is issued by text message to growers in the immediate area in coordination with the IRS. This enables them to check their own parcels in a targeted manner and if the number of lice exceeds the damage threshold, the growers can use specific and selective plant protection products. The damage threshold is carefully established by the IRS since, after all, there is no point to using plant production products below this limit. This helps us prevent the unnecessary use of products.”
Natural enemies
Much research is conducted into the natural enemies of pest insects and how these can help combat pests. Jurgen explains, “Within Green Circles, we are working together with Waarneming.nl and Naturalis to further enhance the ObsIdentify app to make it suitable for beet cultivation. Growers will be able to identify insects in the app based on a picture, so they can determine whether it is a useful insect or a pest. Incidentally, as part of this, we are also carrying out research into sowing barley between sugar beets. Barley is currently often sown in sandy soil to help prevent shifting sands, but is also an important host for natural enemies of the green peach aphid. In itself, this aphid is not harmful to beet plants, but it can transmit a virus that can ultimately cause a yield loss of 50%. ‘Attracting’ the natural enemies of this aphid to the parcel via barley can offer numerous benefits. We are currently researching the effects of this at various locations in the Netherlands.”
Field sensors
Apart from natural enemies, high-tech applications can also help sugar beet growers protect their crops in a very targeted way. “Sensors have already been installed on around 750 Dutch beet parcels that use the temperature and air humidity in the crop to monitor whether the conditions in the parcel are favourable for an infestation of a specific species of leaf fungus. If so, the grower automatically receives notification via BAS that it is time to check the crop for infestation after 7 to 14 days, depending on the type of fungus. The grower can also opt to use a relatively new natural product on the parcel to activate the plant’s defence against the fungus. This is not a miracle cure; spraying with a regular antifungal solution is often necessary after a while. But on average, growers will have to use the solution less often than if the ‘green’ fungicide is not used first. At the end of the day, that makes a difference.”
Sugar beets and climate
Since sugar beets have deep roots – up to two metres long – they are less affected by heat and drought than many other crops. But extreme weather conditions like we saw this past summer show that there are limits to this advantage. Not only that, but climate change makes crops more vulnerable to certain species of leaf fungi. Developing new, less sensitive beet varieties and innovative, green pesticides and monitoring systems can all help beet growers lower the risk.