Duijvestijn Tomaten uses photosynthesis and oxygen sensors for crop optimization Duijvestein is using new Sendot sensors now for the second year in row. Specifically, the photosynthesis sensor on the leaf and oxygen sensor in the root zone. Both sensors provide new insights to optimize growing conditions.
Last year Richard Enthoven, cultivation manager at Duijvestijn, gained his first experience with these new type of sensors.
Plant growth with photosynthesis
The photosynthesis sensor measures the amount of chlorophyll activity and the PAR light on the leaf. This shows how much light has actually been absorbed. The extent to which this happens is closely related to other known growth factors. “In stress situations you see the photosynthesis efficiency clearly decline,” says Enthoven. “We saw this regularly during last years hot summer. By changing set points, such as temperature or moisture deficit, you can see how the plant responds in terms of photosynthesis. In this way you learn what works in order to get the plants to perform at their best."
Oxygen in the root zone
The root zone is of crucial importance for plant growth and plant resilience. On the one hand, water and fertilizers must be available as much as possible. On the other hand, a high oxygen level must be maintained. A high oxygen level in the substrate is important for the root quality, and water and nutrient absorption. Moreover, oxygen has a direct impact on healthy roots, so that the plant can better defend itself against pathogenic microorganisms. Sendot’s innovative oxygen sensor helps to measure the oxygen level in the root zone and gives direction to the search for the best cultivation strategy.
In general, the roots consume oxygen when absorbing water and nutrients. For tomatoes, water and nutrition must be available as much as possible, where sufficient oxygen in the root zone remains. This is important, otherwise water and nutrition cannot be absorbed sufficiently due to lack of oxygen. The watering should therefore be optimally adjusted to the plant needs.
The sensors very often confirm that we are doing well. But not always. When conditions become more extreme, you often see surprising results, “says Enthoven. “We learn from that”. Enthoven notes that new technology and linked insights that give evidence to adjustment growth models.
Enthoven merkt op dat nieuwe technologie en de inzichten die daaruit voorkomen ook aanleiding kunnen geven tot aanpassingen in de groeimodellen waar telers en adviseurs mee werken.