"Growers of everbearing strawberry varieties better bear in mind that the end of spring and the beginning of summer is an ideal period for thrips to invade berry fields. The peak is usually observed around late May/early June, depending on areas," says Julien Mourrut-Salesse, Manager of the Sustainable Crop Management Specialists at Biobest.
A rapid and massive pest attack requires an effective answer. In strawberry, the predatory mite Amblyseius swirskii is a trustworthy beneficial. When thrips is already present on the plants and fruits, A. swirskii actively looks for thrips on flowers, leaves and fruits. But also in absence of thrips, the swirskii mite is extremely useful. Thanks to the application of Nutrimite, Biobest’s 100% natural food supplement made from a special selection of pollen, growers can bring their swirskii army to fighting strength before the pest arrives.
“Nutrimite contributes significantly to a successful preventative installation of swirskii in strawberry. We saw twice the population level compared to a situation without alternative food source,” says Julien. “This strategy is very effective especially against thrips that appear on the fruits. Moreover, a good population of swirskii also helps to control spider mites and whitefly, other important pests in strawberry.”
Practically, Julien typically recommends one swirskii sachet per two (linear) meters of strawberry. Application of Nutrimite every 15 days will ensure a good installation of the mites. In some cases, a second introduction of swirskii may be useful.
In addition to thrips, spider mites and whitefly, strawberry growers may also face aphid attack. Julien: ”For effective aphid biocontrol, Biobest recommends a preventative strategy based on the Aphi-Mix-System, a ‘blend’ of four species of parasitic wasps (Aphidius colemani, Aphidius ervi, Aphidius matricariae and Aphelinus abdominalis) and Aphidoletes-System, containing the gall midge Aphidoletes aphidimyza. Aphi-Mix can be applied when temperatures are above 12°C, adding Aphidoletes from the moment minimum temperatures stay above 16 degrees Celsius. Finally, in case of an aphid infestation, the gall midge and the green lacewing Chrysoperla carnea can be used curatively.”
For more information
Biobest Belgium NV
Ilse Velden 18
2260 Westerlo - Belgium
T +32 14 25 79 80
F +32 14 25 79 82