Clipping tomato or cucumber plants to the high wire, that's something growers are well accustomed to. Photosynthesis efficiency sensors are becoming more important in the greenhouse as well, and the Qlipr from PellikaanQ seems to come in handy there. "We actually use the Qlipr for the exact opposite of what it was designed for, but that's what makes it such a good invention", tells Kevin Tomson with Sendot, which, among other things, develops sensors to measure the efficiency of photosynthesis.
Since the spring of 2019, the mobile photosynthesis efficiency sensor is on the market. The introduction was done in demo greenhouses with orchid trials, but the sensor is now also used in the tops of bell pepper plants, and will also be used in many other cut flower, potted plant, greenhouse vegetable and soft fruit cultivations. Not every crop however, has leafs that are strong enough to fixate the sensor on, so a clever solution was necessary.
"At the advice of cultivation advisors, among others, in our search for good accessories for the sensorkit, we came out at the Qlipr from PellikaanQ", says Erwin Grafe, Commercial Manager at Sendot. "Not only the thickness of the leaf is a challenge, but also the circumstances in the greenhouse like air flows. What you want is a stable measurement which doesn't involve the leaf hanging or moving due to external factors, so you get a representative rendering and valuable data."
Detect and prevent disturbances
That last thing is of course what growers, sensor producers and cultivation advisers want. The more measurements and data, if well used, the better growers can optimize their cultivation in times that everything is more about fine tuning and the profit is more in the details. "With the photosynthesis sensor it is possible to have insight in a day and night cycle in a plant, and to monitor when it is in stress. You can learn from that as a grower, but then the disturbance shouldn't be caused by instability of the sensor setup, of course."
But what makes the Qlipr the best thing for this application? "This is the only clip in its sort that I know, with which we can fixate our sensor properly without damaging leaf or plant", tells Kevin, who has assembled sensors since the start of the company in 2015. "The nice piece of foam rubber goes around the plant, in our case, upon which we use a piece of flexible aluminum wire, where the Qlipr is on. That makes our setup flexible, where many other comparable sensors work with a permanent setup and a brace."
That the Qlipr fixates the sensor good, doesn't mean that growers don't have to look at the sensor anymore. "No, the grower will still need to check all the sensors regularly. It is important to keep up with them. With fast growing crops, the plant can easily grow 20 centimetre per week, so usually you have to move the sensor about as much as you clip the plants", says Kevin.
A grower doesn't need a sensor on every single plant. "If the average grower has one sensor on one hectare, that's pretty good for me", says Kevin, emphasizing that it's nice for PelikaanQ to see that their Qlipr is used in the greenhouse in this way too. "Growers will sure use more sensors per hectare in the future, but it has to happen gradually, plus there are more sensors that need to be taken into account."
The photosynthesis sensor measures plant features, and that deserves more attention than sensors that measure surrounding factors like soil moisture, temperature and oxygen levels at the roots. "The sensor demands more action, but provides a better insight in photosynthesis and growth, so that's more than worth it if you ask us", Erwin and Kevin conclude.