Over recent years, Biobest advisor Arno Hellemons has seen good results using a combination of cucumeris and Orius to control thrips in strawberry crops.
“With this strategy strawberry growers are getting this challenging pest under control,” he said. “Most growers already use Amblyseius-System and/or ABS-System. This provides an excellent start as the cucumeris eats thrips larvae, efficiently tackling the first stage. Introducing this predatory mite into the crop regularly and preventatively provides an effective first line of defence. However, it doesn’t control adult thrips. Orius-System is a valuable addition to the control strategy as it eats all stages of thrips, while also tackling aphids, spider mites and whitefly.”
Hellemons advises growers to pay attention to the ambient temperature.
“Orius develops considerably slower at low temperatures,” he said. “Therefore, when cultivating in tunnels, I recommend waiting until night temperatures remain above 8°C before introducing Orius-System. Meanwhile, greenhouse growers can start introductions now. Recommended introduction rates for Orius-System vary from 2 to 8 units per square metre – with the predator population reaching full strength within 1.5 to 2 months.”
Timely monitoring is also crucial.
“Our Crop-Scanner app can support growers in this,” said Hellemons. “This tool works on smartphones and tablets and is connected to an online web portal. This means all observations in the crop can be brought together and stored – enabling growers, and their advisers, to analyse data online and closely monitor pest outbreaks. In this way, we are able to develop a timely biological control strategy.”
Hellemons also stresses the importance of sticky traps. He advises growers hang 1000 – 2000 Bug-Scan® Yellow NHS traps per hectare.
“Thanks to Biobest’s ‘New hanging system’ with clips, this task has been made easier and more efficient,” he said.