The major culprit in potato cultivation: nematodes

Now that fewer chemical agents are available, it is becoming clear that nematode control in potatoes is not just about what is applied, but primarily about what happens in the soil and the choices made in the cropping plan. Insight into nematodes, their behavior, and their impact on the crop forms the basis for manageable cultivation.

Not all nematodes are harmful. More than a thousand species occur in Dutch soils, the majority of which play a positive role in soil life and the food web. Only a limited number of plant-parasitic nematodes penetrate the roots, feed, and can thus cause damage to potatoes. "In potato cultivation, we are dealing with a relatively small number of species, but they can have a major effect on yield and quality," says Marnix Gijlers, Crop Advisor at Syngenta.

Damage pattern and build-up of nematode populations
Nematode damage occurs primarily underground and is often only recognized late. By feeding on the roots and underground stem parts, nematodes extract energy from the plant that is not available for growth and tuber formation. In practice, this can lead to lower yields, smaller tubers, and quality problems such as cracking or irregular shape. The taste of the potato usually remains intact, but external quality and sorting come under pressure, which is often the deciding factor economically.

One of the reasons that damage is often noticed late is that nematode populations build up gradually and that natural degradation also occurs when no host plant is present. Some species have a specific life cycle and are active only once a year. As a result, a field may appear healthy above ground, while pressure is already increasing underground. When problems become visible, it is often difficult to take corrective action quickly. Much can be achieved by using resistant varieties. However, these are generally not 100% resistant, and some nematodes manage to circumvent the resistance mechanism. Additional measures are therefore necessary.

Difference between plots and the importance of measuring
Not every field reacts the same way to nematodes. Soil type, cropping plan, and variety selection influence how populations develop, and clear differences in susceptibility also exist within potato cultivation. Furthermore, for seed potato growers, the presence of certain nematode species can have direct consequences for cultivation possibilities due to regulations regarding quarantine nematodes.

Because risks vary widely from plot to plot, in-depth insight into the soil is essential. Syngenta is not standing still. To support growers in this transition, the company is investing heavily in field research and innovative techniques. A crucial part of this is the Interra® Scan"In greenhouse horticulture, data-driven management has been the norm for years; in arable farming, we are now moving in the same direction. With the Interra® Scan, we map the soil, the foundation for a healthy crop."

As Gijlers summarizes it: Whoever knows what is going on in the soil is stronger in the cultivation system and can better manage damage.